Last week I found out my local indoor range allows carbines.  It's only 25 yards but its also alot closer than the closest state range.

So.  I scaled and printed the 25 yard sighting target, and drew up a reduced 'A' 10" bullseye target.

Three goals for this session. 

1. See that it fires without issues.  1 round in the chamber. None in magazine.

2. Bench rest two 7 shot groups at the sighting target.

This got modified to 1 off hand and 6 shots bench rest.  Then 7 shots off hand.

(The bench was too low and I wasn't comfortable shooting that way.  Next time we'll raise it)

3. See how I do on the 'A' targets off hand.

4. (yea I know I said three. Get familiar with running the gun and work on good habits.) 

Had one failure to feed which may have related to my loading the magazine off the strip clip.

Groups were OK but seemed like I was losing focus, just a little, and need to work my skills. 

Not sure using a stripper clip to load a magazine would have anything to do with a failure to feed? 

Flip sight.  Although I have been planning to replace the leaf spring, decided to put that off.

Strip clip loading.  I'm not sure either.  Since it was my first time with everything.  The range had no .30 carbine ammo so I brought some of the Korean I bought last fall.  A couple of the guys at the range/gun store have carbines themselves but they were pretty busy.

Posting. You're welcome!  It's fun to shoot.   I definately plan to shoot it more.  I think the state game land range will likely allow shooting from sitting, kneeling, and prone.  

While cleaning the carbine I found the recoil plate was rather loose.  That may have contributed to my groups spreading.    Although I really think it was mostly me.

Be interested in what targets people use.  I liked the idea of a target similar to the military qualification target.  I figured that would provide appropriate sized bullseye as well as a goal for scoring.

Empty beer cans I presume?😆

I use a variety of targets. Some I buy or print out. But being retired I'm on a budget so I repurpose paper plates and used pizza boxes. I love shooting steel and have several types of metal targets. I like the sound they make when I tag them. I live next to a golf course and collect a bunch of stray balls that I shoot. It's fun to see them fly when hit.

Hitting golf balls is impressive! 

Cheap is good :)  At least on stuff that's going to get thrown away.

This was the thread at CMP discussing WW2 and later  and qualification.

http://forums.thecmp.org/showthread.php?t=135497" rel="nofollow - WW2 marksmanship levels: http://forums.thecmp.org/showthread.php?t=135497

The statement about a pay incentive Marines who qualified as Sharpshooter and Expert got my attention. My dad qualified as sharpshooter on rifle (June '43) and I'm sure that extra pay was valued.  Oddly AFAIK he never was trained or qualified on either the carbine or pistol.

And this one had some excerpts showing WW2 and later targets.

https://www.milsurps.com/showthread.php?t=11545" rel="nofollow - 5V targets: https://www.milsurps.com/showthread.php?t=11545

Range Day 5 March 2021.

Outdoors. 100 yards.

Wind fairly calm at first then picking up fairly strong  from the NW  (left to right).  No flags at the range but forcast was for wind in the 10 to 20 mph range.  I did not attempt to compensate. 

Part 1.

Warmed up with prone, slow fire.   Army A 5V Centers with 12" bullseyes

Seemed to be hitting low when using 6'o'clock hold.

The binoculars I brought were inadequate to see hits on the bullseye. 

Next was a home made sighting target.

Plan was 7 rounds with the sight set for 100 yard. then 7 rounds with the sight flipped for 300 yard.

Good news was pushing of the rear sight to the left after last session brought the shots on center.

Vertically the top of front sight seems pretty much to be point of impact.  I can live with that. 

However when I went to change magazines (range rules are 6 rounds max) , I noticed the rear sight had flipped to 300 yards.  Soooo, that probably explains why there's only 5 shots at the bottom of the target.

Leaving it for 300 placed next 7 above the target.

While waiting for the other shooters to get done and call clear, I let my buddy shoot a couple magazines.  I think that's why there are more than 14 shots on this target.  My fault I forgot to flip the site back to 100 yards and I didn't notice until he was just finishing.... whoops!

More later.  need to finish cleaning.

part 2.

This was my attempt to run the 100 yard qualification tests from Table III of the field manual.

I was about 15 seconds overtime on 4 rounds standing, change magazine 4 rounds sitting.

And I was about 10 seconds overtime for the standing to kneeling.

Scores were consistantly 19 out of 20, but they wouldn't have been on WW2 era 10" bullseye 'A' targets.

All shots from this test are circled in blue. 

Green and umarked holes were from reuse of the targets but the targets started flapping around so many of those were shots attmpted when the target was momentarily still.  Sometimes just got to roll with the situation...

Had the second failure to feed when sitting on the second, aborted, run on the left side targets.

Another issue that probably should be addressed is the recoil plate slightly loosened.  Before disassembly for cleaning there was full turn of the screw before it felt snugged.

I'd be happy with those results.  

Thanks guys.  I don't have the sort of experience with centerfire to compare.  Its one reason I thought using the 100 yard qualification tests would be a good place to start.  

Been thinking about the shots hitting low.  Is there any way that could happen if both front and rear sight are original to the reciever and barrel?   I'm thinking this probably is a clue this is not the front sight it was zeroed with at the factory.

No tips on Barrel hang ?

No tips on Recoil Plate to Receiver lock up ?

Barrel Band fit ?

Recoil Plate coming loose during shooting sessions ?

I'll wager the man can tighten those groups by a minimum 30%

@ Matt_X......  PM Sent  

Ch-P777

NRA 50' Slow Fire Target

Barrel hang seemed good.

I'm going to make a work rack to hold the carbine and then can check this more carefully.

I've been a little concerned about crushing the woodwhen tightening the recoil plate.  The wood under the plate looks OK.  But the threaded escutcheon is recessed and thats what felt like it might have some give.  

I can eyeball the barrel to see if there is any obvious bend.  Removing it from the reciever is well above my grade or equipment here.

As the weather gets nicer, I need to dig my two carbines out and get them to the range.

I have to laugh because I remember rattling off that mag .. Circled Group.. As fast as I could pull.

When I looked at the group as I set it on the bench for her. I slid the peep down to the 100yrd setting.

After her getting a feel for the trigger break and seeing her hits.

She made her corrections and put pretty much everything else in the black.

I started her shooting rim fires at age 7. 

I think she would have had better results had I not had her shooting some slugs 1st from a Rem 870 12ga.

She's very skilled with her hand guns. The target she's posed next to was shot from 35yrds with .38Spl 158 gr SWC  and .357 Mag loads. Shot standing and kneeling. She complained that they didn't print the same. I was mixing the loads around and sometimes put in a snap cap to catch her flinching.

No fear in her, she was a Nationally Ranked Equestrian in College and before that a Multi State Champion in Barrel racing, Western Reining and English Dressage.

I was very proud of her accomplishments but I sure don't miss the $$ Costs.

The horses are the cheapest expenditure after you figure in all the different saddles, tack, show gear, practice gear, travel expenses, horse trailers and motor home... etc + Hospital bills- See below-

I was nearly stomped to Death by a Thoroughbred of hers I was leading in to the barn along with his pasture mate when a trespassers gun shot rang out and spooked 'Big Will'. A former Track horse that she 'Adopted' and trained herself. Suffered some broken ribs and a concussion from that loosing battle.

When we found out from the owners of the stables we boarded at were having financial problems, we invested in as percentage partners. Got lucky and got the Michigan State University Women's Equestrian team to board and train there. Ended up buying those partners out and later after my Daughter went in to the Navy we sold out while having full capacity. A profit finally !

She now works for the DOD along side of many of her former commanding officers near D.C.

The End

I'll return your PM later tonight or in the morning.

I've got a Date with a Marlin model 60 and new scope to tweak.

Sorry going Off Topic, hard not to brag on a Daughter.

Ch-P777

Finally had a chance to clear the workbench and get back to this.

When I removed the barrel band, there was no upward spring. 

Checked the fit with the recoil plate.  Its tight, but maybe it should be tighter?? 

Reinstalled and tightened the recoil plate, got another quarter turn on it without feeling it was going to strip or damage anything.

Barrel came up a little (see picture), but snugs down in without bouncing back.

Sorry for my late reply. 

I've been on a Successful search mission for fellow member JD aka Jond41403 

Yep, If it shoots high aim low, if it shoots low aim higher. Same goes for left and right! Kentucky Windage!

I'm not too familiar with using crazyglue on wood.  I see it in the catalogs but its one of my typical adhesives or consolidants.  I'll look into it.  I've got some 'old brown glue', tightbond and epoxies.

After dinner I'll check how much gap there is under the barrel band.  Because it and the sling swivel are reproductions I'm perfectly willing to file the latter or add some shimming. 

I was looking at type 1 band  photos to see if there should be a gap or a spacer.  Pretty sure there's no type I drawings in Kuhnhausen.

http://www.uscarbinecal30.com/stockparts.html" rel="nofollow - http://www.uscarbinecal30.com/stockparts.html

Compare to the bottom front edge of your pictured band.

Krazy glue works well for seeping in to small areas and doesn't leave a hi build up, unless reapplied over dried coats.

Ch-P777

I get the idea.  That's a lot better fit.

Due to the shape of the repro band, without taking it off, probably the only thing I can do that won't dent the stock is slip in some cardboard or similar material.

Most of the outer band contact with the stock is on the rear and right.

The bottom of the band has a bit of a peak to it which will be difficult to smooth out while on the gun.   A .002" feeler gage will just slip through there, and on the right by the spring, .003" easily slips through.

What I had been thinking was to reduce the hieght of the swivel (arrows). 

Perhaps a real Saginaw band would be better...

Example from club web page.  (Ignore arrow pointing to spring pin.) 

@Matt_X,

Hopefully this will point out what I'm trying to say.

Object is to Shim to get the Barrel up.

The BLUE area if shimmed will put a Downward Pull on the barrel.

The YELLOW area when shimmed will push the barrel up. A few build up layers of Tape works well.

Or The Stocks barrel channel could be shimmed where it would contact the barrel band (YELLOW Area)

It's Possible after shimming on the Band or in the Barrel channel nose that the Hand Guard wont fit as snug to the Bands lip. Because of either shimming method 'Pushing' the Barrel upward.

To tighten loose Hand Guard:

See GREEN-  Using Tape or even a Flat leather bootlace in this area will snug the Hand Guard up.

Placed on the Band or over the Hand Guards front lip.

Another option is to Bend the Bands Ring over the Hand Guard Lip. I try not to do this incase I want to use this same Action in another Stock.

** Note Where these Shim locations are Avoids the Heat of the Barrel** 

** Shimming in the GREEN and YELLOW areas should pull the slack from the Bands outer ring**

I really hope this 'Example' works. I've spent an hour trying to down size this picture and add the colors  

Charlie-P777

Charlie,

I see. I see.

 I thought it was the lack of good contact.  Same thing 35 Whelen was describing.

You're actually suggesting that raising the barrel slightly could bring the POI up.  Yes?

Regardless of where the barrel is, the sights will move with the barrel, so it doesn't change a thing. These suggestions are things that will stabilize the action and possibly make it more consistent (print in the same spot). If the barrel is slightly bent in one direction or the other by bedding it, it will certainly change POI, but not likely enough to move the impact by inches.

I hear that loud and clear!

What I don't understand was the line about bringing the barrel up.

Why not bring the barrel even more snug into the stock?

My perspective is the gaps and uneven clamping creates a spring that lets the barrel move with every shot.  That's why my focus was on the outer band (the blue area).  Taking up all the slack in there seems like it would only do good.

The early Mini 14 exhibits similar issues. Various devices have been marketed to improve it, such as harmonic balances, braces and even something as simple as adding a flash-hider. Both these guns exhibit similar issues due to the skinny barrel. Ruger eventually addressed the problem with a thicker barrel.

Finally.  Morning was nice and calm.  Not too busy at the range.

Going to leave the sights alone for now.  Might push the rear one over a little more if I keep grouping them right.

With the smaller bullseye on the SR1 targets I had to work on focusing on the front sight.  Basically I think at this point its more me than the carbine. 

One FTF - this time I noted the magazine and will go over it one evening this week. 

The empties were flying!  I could hear them hitting off the underside of the roof.    Unfortunately I couldn't recover the majority.  No idea where they went - and I looked and looked.

Front band didn't loosen.  My cold smithing seems to have worked well.

Recoil plate screw may have backed off a 1/16.  I need to check my notes.

POA was the center of the bullseye.  Next time, at least on a SR1, I'll use 6 o'clock.

Sitting & kneeling. Two sets each. 

Offhand, 2 sets.  That's all me there - not the carbine!

Been a while.

Range was somewhat busier. 

Took a lane next to an M1 rifle.  :)  

Prone and sitting was a little cramped.  

No FTFs.   Some shells ejected forward, some back.  Got two in the forhead and decided to put a hat on. 

I'd say within my ability yesterday both the IMI surplus and the Korean surplus shot about equally well.

  Your targets state that fired the groups prone, unsupported. If you're a right handed shooter a good tight sling used as it would be in High Power could very well move your POI to the left. Just a little food for thought.

 

I'll have to try that and/or shoot from the bench to isolate how much is me.

I'm sure having a coach would help too!

I was a little too confident (cocky?) when I got there.

My plan was to compare the IMI and then work on the other three positions needed for CMP match.

There's two clubs within reasonable distance that have CMP matches once a month.  I need to check on the sling rules and course for carbines.   Not sure if I'm quite ready for timed fire.  I think I can get the kneeling in 60 seconds but it will be very close.  Prone and sitting I'm pretty sure I need to pickup speed.  And I dont want to do that until I improve my form. 

But I could still use the sling when practicing and comparing.

With the crammed position and the loose denim shirt the butt wasn't sitting nice in my shoulder. 

The previous I used the position next to the benches with seats.   You can see my targets and extra cardboard backer under the table.  This time I was in the lane to the right (angled arrow).   But the block on that table comes further forward because there are no seats.  oops.

Here's my other three targets for the day.

Both kneeling and sitting I took a little time on the first few shots and then tried to shoot quickly including a quick magazine change.

  Just an FYI, in a match, kneeling and sitting positions are not two separately used positions. You choose one or the other and in my very limited exposure I've never seen anyone use the kneeling position. 

  Here's a link to the rules for M1 Carbine matches (scroll down to page 28)-  https://docs.google.com/document/d/1_uM6kLBDEIhAtWYdIh16-Bc5gcVy3Rj0ts-aifR2Blg/edit" rel="nofollow - NM Rifle Program - Draft 2021 - Google Docs

  I would strongly suggest, if possible, you learn and polish the basic principles of shooting from a bench. Once you're shooting nice groups from a bench, THEN start working shooting offhand, sitting and prone. I helped coach our 4-H smallbore team and it wasn't practical to start the green shooters off at the bench, so we'd start them shooting prone, but still the shooter must learn how to shoot from prone and the principles of marksmanship at the same time.

   Here's a link to a pretty good guide on service rifle marksmanship-  https://nfga.org/wp-content/uploads/highpower/basic_highpower_info/SR_Shooting_Guide_AMU031204.pdf" rel="nofollow - SR SHOOTING GUIDE.PDF (nfga.org)

 Your 100 yd. targets really aren't bad at all, keep it up!!

Thanks!

I have the Canadian and US Army books downloaded as well.  I actually found the Canadian one (Shoot to Live) illustrating the "Johnson method" a little more helpful.  But its almost entirely focused on firing prone.

Sling rule for M1 carbines is under 5.3.2:

https://thecmp.org/wp-content/uploads/CMPGamesRules.pdf?vers=121720" rel="nofollow - https://thecmp.org/wp-content/uploads/CMPGamesRules.pdf?vers=121720

In the equipment section is states only M1 carbine slings (or copies) may be used.

I find it ironic that in general I've been shooting better in kneeling than sitting.  When I was a teenager I was pretty good in sitting but then stuggled to make my kneeling targets.  I might have used a crossed leg sitting position with the 22.  Gee. You'ld think I'd remember.  LOL  Of course the jr rifle program is all slow fire - plenty of time to get in position and take the shots, and recoil wasn't a concern. Remington 511 with peep sights or 513T

Sitting Rapid fire was usually my best position and I often scored well into the 90's with my best being a 97-2X. The SR-1 target helped a lot!

What's the advantage of the SR-1?   I thought the reduction in size matched the reduction in distance?

Where you guys shooting service rifles or carbines (or both)?

I've got a long way to go to get that good in off hand.  You can see my scores on the first above.  My offhand from April gnerally looks better (as do most of my targets) but cant score them as I that was before I read the rules and was shooting 14 rounds per target.

In what used to be the junior marksman program, standing was taught more like you'd expect for .22 bullseye competition.  Thats a rather different stance, not that I ever mastered it.  I took a look to find out more about the program and sadly it has apparently dwindled to hardly any participation.   :(  

see https://firearmusernetwork.com/2011/09/01/history-of-the-marksmanship-qualification-program/" rel="nofollow - https://firearmusernetwork.com/2011/09/01/history-of-the-marksmanship-qualification-program/

My patches are labeled 50 Foot, not Junior, so I guess there were several changes in the program but it was pretty universal at the time.  I started at the NJ School of Conservation summer camp an and later continued with a local YMCA.   

 

  There's no advantage to the SR-1, it just has a generously sized with the 9, 10 and x-ring being in the 6" black. It's the reduced target that is used for 100 yds. 

 I'll tell you light rifles light the Carbine are difficult to shoot offhand because they tend to wave and sway around. When I was competing in High Power I was using a modified Swiss K-31 and light cast bullet loads. Due to the weight of it, that rifle just sits there in offhand.

 For offhand practice I took a manila folder, drew a black bullseye (actually a small dot) on it, scaled to the distance (30' if memory serves) and taped it to the door of a metal cabinet in my shop. I would dry-fire at this in the offhand position and it made quite a difference in my scores....when I actually did it!

 

 

These are from yesterday's match.  Course A: 5 to sight. 10 prone slow, 10 prone rapid, 10 standing.

Unfortunately we were shooting into the sun, and only the far right lanes had good shade from the trees.  The bright metal on the front sight's top edge made it a lot more difficult to focus.  Looking through the rear sight it seemed to have lint in it.  I think that was just an illusion.

With the first sighters I was aiming at the left center of the bullseye to compensate for the front sight.  But either the sight was more vertical, or the lighting and my sight alignment were such that POA seemed to be prtty close to POI.  

It would be nice to have a coach watching to see if I was making changes to my cheek weld or other body mechanics.  But I think my poor shooting in rapid fire was because I couldn't clearly define the front sight.  But it is interesting that whole group is also low.

Would really love to come up with an effective way to blacken the sights where the finish has been lost.  One of the pistol forums mentioned a black india ink.  I might try that. 

http://forums.thecmp.org/showthread.php?t=146065" rel="nofollow - Blackening the front sight questions - CMP Forums (thecmp.org)

Thank you gents.

I made a little kerosene smoker out of rifle shell, a cloth wick, and a 45 acp shell as a cap.

  I can also clearly see the top of the front sight - which tells me the top isn't angled down sufficiently.   It may get filed down even though some consider that taboo.   We'll see.  It's a somewhat 'restored' carbine already.

Correction on the rapid fire target. Seems I can't add to 49.  Still way below where I ought to be able to score.

I posted this in the thread about IMI softpoint.

(Their FSJ is pretty much the same.)  http://www.federalpremium.com/Ballistics-Calculatorhttps://www.federalpremium.com/Ballistics-Calculator" rel="nofollow - https://www.federalpremium.com/Ballistics-Calculator

edit: This is probably worth further discussion both on practical and historical application.

According to Federal's graph, if zeroed at 100 yds, then point of impact at 25 yards will be just a hair under point of aim.  

I entered 1.5" for sight height when I used the calculator.  Maybe that makes a difference here.

I don't know the history of this test target.   Its in Kuhnhausen on page 107.   (See the first post of this thread for an example I printed.) It appears in the 1953 TM9-1276 in Chapter 4 Repair and Rebuild  section 25 Firing Test (c) Targeting - but not in the 1947 TM9-1276.  

The hieght I used  for the graph in my previous post (above) was 1.5" and intended for comparison with IMI's ballasitics table.   According to the Kuhnhausen unfiled front blade hieght above barrel centerline is supposed to be .785" minimum.

Using Federal's calculator, changing the sight hight to .83" moved the muzzle (and angle?) upward relative to the target centerline.  This changes the 25 yard point of impact from .1" below target center to .4" above center.   Changing the blade hieght to .785" results in the same .4" rise at 25 yards

Perhaps barrel length and other factors account for the addtional shift on the 25 yard ordnance target.

Interesting!

Out of curiousity, lets see what Federal's calculator shows with a .785" high sight zeroed at 25 yards compared with 100 yards.

PS. Here's the correct URL http://www.federalpremium.com/Ballistics-Calculator" rel="nofollow - https://www.federalpremium.com/Ballistics-Calculator

Graphed using Excel (office 95)

I think the short answer is 100 yards.

Aiming was based on 6 o'clock hold.  Which means for targetting we need to know the bullseye diameter.  

Maybe someone can answer this for wartime production targetting.

However the WW2 era field manuals state qualification target 'A' had a 10" bullseye.

This is the sighting target  in the 1953 Technical Manual for 100 yards

I don't know if its coincidence or not, but the Army 'A' qualification target went from a 10" bullseye to a 12" bullseye around this time.   Makes me think the 1953 sighting target may be more generous than the original production requirements.

And this is the 25 yard version from the same manual.  Its a reduction by 4 of the 12" center.

The shots at 25 yards needed to hit 3/4" higher for the 100 yard zero to be correct (with a 6 o'clock hold).   So I's say if your 25 yard group is slightly above center, it should be pretty close to centered at 100 yards.

 With the original flip sight, the short range zero was 150 yds., the long range, 300 yds. I think 150 yds. is a pretty good compromise. I'm not super picky as long as when using the 100 yd. sight setting, my 100 yds. POI is POA to +3" or so.

 Here are some tables that might help you decide.

 

Yes. That makes sense.  

If you are aiming at target center, then a group about .4" up will give provide a zero at 100 yds.

If you are aiming using 6 o'clock hold, its the same but requires a 25 yard bullseye scaled down by roughly 4 from the intended 100 yard bullseye.

For example the Army 'A' target was 12" so they used a 3" bullseye at 25 yard.

The current competition SR-1 black is just over 6" diameter so a 1.5" bullseye at 25 yards would be the scaled down,

Shells I picked up at the range. Cloth was cotton rag (t-shirt? or sheet?). Kero I keep on hand for assortment of tasks.  Not that much kero in it.  Just enough to wet the wick.  Experiment a little.

When the action is mounted in the stock and the recoil plate torqued, the barrel at the end of the stock nose should ride slightly off the stock-channel. Think of it as inletting a target rifle stock so that the barrel does not touch any of the wood.

This is one of the finer points of accuracy, but to be honest….I have never worried about it. These competition shooters and serious accuracy enthusiast might can benefit, my goals are coffee cans at 40-50 yards. 

A couple pages back Charlie (painter777) described it pretty well I thought.

The way I understand it, when the reciever is installed into the stock, it should lock snugly into the recoil plate.  So snug that without a little push the barrel sits a little bit above its final seated position.

There is going to be a gap at the very front of the stock.  It's the inner barrel band that contacts the inside of the stock.  There may even be some impressions in the wood.

"Your barrel hang and Recoil Plate lock up to Receiver look good to me.

I’m saying you can’t expect much more from a carbine than you can a stock pencil-barreled Mini, but likely a little better.

For some reason....my pix disappeared. Here it was.

I think it’s “how”’the muzzle is worn. If it is worn the same 360-degrees and to the same depth all way around….there is always some rifling farther down in the bore. That’s my theory anyway, for what it’s worth. This barrel shoots better for me than any other carbine I shoot or have shot, even one measuring .299 and another with an ME of 1. It’s repeated over and over, always shoot a barrel before you replace it based on an ME measurement. The crown is also very important. Counterboring could probably solve most ME problems.

I share tables with a couple of friends, but we limit our shows to Jackson, Natchez and Laure.

Yesterday's trial of my Midway Underwood had a couple feed failures, and also I think light strikes. 

:(   I'll start a seperate thread on the functional issues.

Got a nice spot on the range before it got crowded.  Temperatures were perfect - in the 50s? and no wind to speak of.   To keep things simple I aimed center of bullseye the entire day.

With this carbine my shots are much more centered left to right than I've been with my SG (see earlier posts here). 

First 5 shots were with the sight set to 200 yrds.  I thought these would group high - just above the bullseye, but they didn't!  If anything they seemed to be a little low.   Moved the adjustment down to 100 yards and left it there for the rest of the morning.  Only fired 19 shots because one cartridge failed to fire.

Next tried something new for me, shooting from the bench.  Used a box to provide a little bit of support under my left hand.  Then later shot 5 without support and that's the group the low.  I think this is a clue that either I'm pulling down or placing my eye/cheek inconsistantly.  Need a coach!

Used up a couple of partial clips, hence the shots fired not a multiple of 5 (my standard now).

Photography note.   To get better contrast photographing the targets at home, I hung an old blue sheet over a curtain rod in a window. Then clipped the target onto the sheet. 

My offhand shots were all low - that's me, but so were my sitting and prone rapid fire, the latter really strung downward.  This is why I'm thinking that I may be pulling the forestock downward or changing where I place my cheek on the stock (closer to the rear sight)

Underwood (Italian return). Surplus PSD 86 FMJ.

Temperature just above freezing when I arrived but was warming quickly.  No wind.

100 yds, SR-1.

Worked on some different things.   The lighter smoother trigger is nice, although I haven't figured out how to make it work for me in off-hand.

 

Can you show how much drop changes with ammo that has significantly lower muzzle velocity?

Lets say 1900 fps.

Am I correct this is only an inch or so at 100 yards?

Are there other factors besides velocity that can make point of impact less consistant with less consistant ammo?

35 Whelen wrote:  With the original flip sight, the short range zero was 150 yds., the long range, 300 yds. I think 150 yds. is a pretty good compromise. I'm not super picky as long as when using the 100 yd. sight setting, my 100 yds. POI is POA to +3" or so.  Here are some tables that might help you decide.

 You are correct, the difference is actually less than 1"-

 There are other things that can change the POI, such as not using your natural point of aim, sight picture, et al.

  You figured exactly why I was asking!  

Last weekend's match I got 87 prone (OK), 71 prone rapid (big improvement but still grouping off the center), and 53 off hand ( ).   My thinking was that changing ammo isn't going to change those results much.  Maybe a little in prone, but not rapid or off hand. I've shot standing in the 70s so I know I can do much better there.

The other thing its helpful for is knowing that if I do change ammo, the change in POI isn't going to be more than an inch or two at 100 yds.  If I see gross change, its something else, probably me.

I think that's right looking at the tables 35_Whelen posted.  Path is bullet position relative to line of sight.  With taller sights the initial position will be further below that line.  Drop is relative to the muzzle.

Looking back at the table from Federal's on-line calculator, there Drop is relative to line of sight.

I experimented with different sight heights and the taller sights increase the initial 'drop'.