The Carbine Collectors Club

Click on the image above to learn more about the M1 Carbine


Forum Home Forum Home > The Club > Safety/ Accuracy/Shooting/Ammunition/Care and Maintenance
  New Posts New Posts
  FAQ FAQ  Forum Search   Register Register  Login Login


Milsurp OAL vs SAAMI OAL

 Post Reply Post Reply Page  12>
Author
Message
Sawbones View Drop Down
On Point
On Point


Joined: Mar 04 2022
Location: Texas
Status: Offline
Points: 109
Post Options Post Options   Thanks (1) Thanks(1)   Quote Sawbones Quote  Post ReplyReply Direct Link To This Post Topic: Milsurp OAL vs SAAMI OAL
    Posted: May 20 2022 at 11:48am
SAAMI = Sporting Arms and Manufacturing Institute

Had the opportunity to Chrony some milsurp ammo to compare w/ reloaded 30 carbine ammo of a fellow Forum comrade.

The reloaded ammo OALs were all 1.672"-1.675"  and every one of the rounds jammed when chambering; tip of projectile hanging up on the rim mouth of the chamber. Curiously the milsurp stuff, namely  Evansville Cartridge Company 1944 and Lake City 1952 all measured 1.665 +/- 0.002" all chambering beautifully w/o 1 jam.  Likewise the off-the-shelf Sellier & Bellot ammo OALs measuring identically to that of the milsurp.

Observation: 
SAAMI recommended OAL for the 30 carbine cartridge is 1.680".
Milsurp  obviously much shorter at 1.665" +/- 0.002".
My carbine will not chamber any cartridge OAL > 1.670"

Seems reasonable to me the shorter OAL of the milSURP ammo is in reality the actual milSPEC (military specification) for the USGI carbine and the longer SAAMI OAL spec is standard for the currently manufactured non-USGI commercial 30cal carbines.

Make sense?

Perhaps if some of you are having chambering issues w/ longer OAL ammo you might consider a shorter cartridge.

I can see where some of you may be rolling your eyes thinking "Where did this moron roll off the cabbage truck" but this is quite a revelation to me, solves my chambering issues so I felt compelled to relay this to other folks on the Forum.
The best thing about this group of candidates is only one of them can win. Will Rogers
Back to Top
W5USMC View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: Apr 29 2017
Location: Missouri
Status: Offline
Points: 2533
Post Options Post Options   Thanks (0) Thanks(0)   Quote W5USMC Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 12:02pm
SAAMI= Sporting Arms and Ammunition Manufacturers' Institute
Wayne
USMC Retired
NRA Life Member
Back to Top
floydthecat View Drop Down
Hard Corps
Hard Corps


Joined: Oct 13 2016
Location: Mississippi
Status: Offline
Points: 1655
Post Options Post Options   Thanks (0) Thanks(0)   Quote floydthecat Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 12:08pm
Not that unusual to hear about carbines with chambering issues using some ammo. There was a change in chamber dimensions early on, which likely contributes to the issue as well as varying bullet profiles. Sometimes SAAMI specifications can seem like a suggestion. 


Back to Top
Sawbones View Drop Down
On Point
On Point


Joined: Mar 04 2022
Location: Texas
Status: Offline
Points: 109
Post Options Post Options   Thanks (1) Thanks(1)   Quote Sawbones Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 12:49pm
Floydthecat again I agree w/ you.  The 1.680" OAL is the MAXIMUM OAL for the 30 carbine.  I suspect anything longer may allow the bullet to encroach into the lands which causes other problems. 
To clarify:  The SAAMI 1.680" OAL is not the standard OAL" for the 30 carbine cartridge; just don't go longer than 1.680".  Trial and error OALs for your carbine to determine which OAL it likes.  I'd begin at < 1.670".

Again, all the 30cal milsurp I've measured was 1.665 +/- 0.002".  All chambered beautifully in my USGI carbine.

Incidentally:
The Evansville 1944 WWII vintage ammo Chrony'd at 1,954, 1,931, 1,921 and1,925 feet/second which is a pretty tight range for any ammo.

The Lake City 1952 Chrony'd at 1,963, 1,967, 1,929, 1,957 and 1,971 feet/second which is pretty tight.

The Sellier & Ballott Chrony'd at 2,045, 2006, and 2,071 Which is pretty crappy when compared to milsurp.
The best thing about this group of candidates is only one of them can win. Will Rogers
Back to Top
Matt_X View Drop Down
Grunt
Grunt


Joined: Nov 10 2020
Location: Phila, Penn
Status: Offline
Points: 573
Post Options Post Options   Thanks (0) Thanks(0)   Quote Matt_X Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 1:07pm
Thank you!  I for one really appreciate the velocities on both the historical and current ammo. 
How far out was the chronograph? 

Back to Top
floydthecat View Drop Down
Hard Corps
Hard Corps


Joined: Oct 13 2016
Location: Mississippi
Status: Offline
Points: 1655
Post Options Post Options   Thanks (0) Thanks(0)   Quote floydthecat Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 1:14pm
Originally posted by Sawbones Sawbones wrote:

The Sellier & Ballott Chrony'd at 2,045, 2006, and 2,071 Which is pretty crappy when compared to milsurp.

Expand a bit on why you consider the S&B crappy? It’s faster than the other stuff you tested.

I shoot a lot of S&B in several calibers and in every case, it is hotter stuff. The 9mm is consistently warm at around 1260fps on average. Military grade stuff runs closer to 1300fps, but the S&B is right up there with it. I have never shot any 30-carbine S&B though. I just find S&B ammo to be warmer in the calibers I shoot it in and it’s not rated +p. 
Back to Top
Sawbones View Drop Down
On Point
On Point


Joined: Mar 04 2022
Location: Texas
Status: Offline
Points: 109
Post Options Post Options   Thanks (1) Thanks(1)   Quote Sawbones Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 1:45pm
Matt:  Chrony was 8 feet from muzzle
The best thing about this group of candidates is only one of them can win. Will Rogers
Back to Top
Rebel92 View Drop Down
Grunt
Grunt
Avatar

Joined: Jul 20 2021
Location: Hattiesburg, MS
Status: Offline
Points: 510
Post Options Post Options   Thanks (0) Thanks(0)   Quote Rebel92 Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 2:09pm
Awesome information. It’s amazing that ammo that old still shoots like it did yesterday! Thanks for sharing!

I for sure have one carbine that I am only able to shoot mil surp ammo out of, and i bet it’s because it doesn’t like the longer profiles of most commercial ammo or the fatter projectiles in the Armscor
Back to Top
Sawbones View Drop Down
On Point
On Point


Joined: Mar 04 2022
Location: Texas
Status: Offline
Points: 109
Post Options Post Options   Thanks (1) Thanks(1)   Quote Sawbones Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 2:21pm
Floydthecat: 
I am sorry my statement inferred Sollier & Ballott ammo is crappy, or inferior.  I simply stated the wide range of velocities of of the Sellier & Bellott (65f/) is crappy when compared to that of the milsurp Evansville 1944 (33f/s) ammo and Lake City (42f/s).  It was an opinion derived from decades of competition reloading and shooting.

Velocity is a function of pressures..
The wide variance of velocities adversely affects downrange accuracy.
Hotter loads does not necessarily bestow better accuracy.
Frankly, I am satisfied w/ S & B ammo but if I were going to a 30 carbine competition shoot by all means gimme a coupla bandoliers of Evansville 1944!
The best thing about this group of candidates is only one of them can win. Will Rogers
Back to Top
Matt_X View Drop Down
Grunt
Grunt


Joined: Nov 10 2020
Location: Phila, Penn
Status: Offline
Points: 573
Post Options Post Options   Thanks (0) Thanks(0)   Quote Matt_X Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 2:22pm
Thanks.  I figured it was prety to close to muzzle, but its always good to check.  Some place I recently read an explanation of why the military velocities WW2 era were much further out.  It had to do with the method of measuring velocity - which if I recall correctly involved high speed photography but in any case required the breaking of two planes at a given distance apart.

Anyways its interesting to have some performance data of WW2 ammo to compare with using the same type of testing.

FWIW, obviously a different chronograph and location, the S&B velocities measued by -Steve-  in 2009 had a spread of 44 fps over 10 rounds.  Posted here: https://forums.thecmp.org/showthread.php?t=2967  item 8)



Back to Top
Sawbones View Drop Down
On Point
On Point


Joined: Mar 04 2022
Location: Texas
Status: Offline
Points: 109
Post Options Post Options   Thanks (0) Thanks(0)   Quote Sawbones Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 2:34pm
I for sure have one carbine that I am only able to shoot mil surp ammo out of, and i bet it’s because it doesn’t like the longer profiles of most commercial ammo or the fatter projectiles in the Armscor

Hey Rebel, I agree.  Ya might seat that stuff down to ~1.665 and see what.  Might remedy your dilemna
The best thing about this group of candidates is only one of them can win. Will Rogers
Back to Top
Rebel92 View Drop Down
Grunt
Grunt
Avatar

Joined: Jul 20 2021
Location: Hattiesburg, MS
Status: Offline
Points: 510
Post Options Post Options   Thanks (0) Thanks(0)   Quote Rebel92 Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 2:43pm
Floyd, what is “+P”
Back to Top
Sawbones View Drop Down
On Point
On Point


Joined: Mar 04 2022
Location: Texas
Status: Offline
Points: 109
Post Options Post Options   Thanks (0) Thanks(0)   Quote Sawbones Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 3:01pm
FWIW, obviously a different chronograph and location, the S&B velocities measued by -Steve-  in 2009 had a spread of 44 fps over 10 rounds.  Posted here: https://forums.thecmp.org/showthread.php?t=2967  item 8) 

Hey Matt:  I went on the above thread.  A very comprehensive treatise on the 30 Carbine!  Covers everything one would need/want to know.  I recommend it to all Forum folks.
The best thing about this group of candidates is only one of them can win. Will Rogers
Back to Top
Smokpole View Drop Down
Hard Corps
Hard Corps
Avatar

Joined: Oct 21 2019
Location: Madison ohio
Status: Offline
Points: 776
Post Options Post Options   Thanks (0) Thanks(0)   Quote Smokpole Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 4:39pm
+P is a higher pressure ammo used in more strongly built firearms. It delivers higher pressures and higher velocities than regular ammo and isn't considered to be safe in many older firearms.
OGCA Life member
NRA Life member
Ashtabula Rod and Gun Life member
Back to Top
floydthecat View Drop Down
Hard Corps
Hard Corps


Joined: Oct 13 2016
Location: Mississippi
Status: Offline
Points: 1655
Post Options Post Options   Thanks (0) Thanks(0)   Quote floydthecat Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 6:36pm
Originally posted by Smokpole Smokpole wrote:

+P is a higher pressure ammo used in more strongly built firearms. It delivers higher pressures and higher velocities than regular ammo and isn't considered to be safe in many older firearms.

Of course that’s true. + designates an overpressure round. I only mentioned S&B because it is strong ammo, but not labeled as +p. I suspect some stuff labeled +p is not as strong as SB9A.
Back to Top
Smokpole View Drop Down
Hard Corps
Hard Corps
Avatar

Joined: Oct 21 2019
Location: Madison ohio
Status: Offline
Points: 776
Post Options Post Options   Thanks (0) Thanks(0)   Quote Smokpole Quote  Post ReplyReply Direct Link To This Post Posted: May 20 2022 at 8:38pm
With some of the current powders, it is possible to deliver higher speeds with the same amount of pressure delivered over a longer barrel burn time with slightly slower burning powders like AA9 for example. Case capacity limits the amount of powder, but burn rates can alter the pressure curves quite a bit. I've recently loaded a batch of 115 gr bullets with safe charges of AA9 but haven't had a chance to chronograph the loads yet. I do expect higher than normal velocity, but no increase in pressure signs.
OGCA Life member
NRA Life member
Ashtabula Rod and Gun Life member
Back to Top
floydthecat View Drop Down
Hard Corps
Hard Corps


Joined: Oct 13 2016
Location: Mississippi
Status: Offline
Points: 1655
Post Options Post Options   Thanks (0) Thanks(0)   Quote floydthecat Quote  Post ReplyReply Direct Link To This Post Posted: May 21 2022 at 7:15am
I have never used any AA9, but Hodgdon says H108 is the same as AA9. I load H108 based on AA9 load data and it is a super good powder to handle. Nothing else I have meters and handles as well. I load 13-grains under a 110-grain bullet and have been completely satisfied. I have tested AA7 and it does work, but is a bit faster, yet about the slowest powder you can use in 9mm. I don’t use AA7 routinely, but noticed no ill effects from the few loads I tested. I might use AA7 in carbine loads when I can’t find anything else and I loaded it a bit lighter than H108/AA9. Cycles fine, brass and primers from fired cases looked just fine…no overpressure signs.
Back to Top
David Milisock View Drop Down
On Point
On Point
Avatar

Joined: Aug 03 2019
Location: USA
Status: Offline
Points: 275
Post Options Post Options   Thanks (0) Thanks(0)   Quote David Milisock Quote  Post ReplyReply Direct Link To This Post Posted: May 21 2022 at 8:50am
Originally posted by Smokpole Smokpole wrote:

With some of the current powders, it is possible to deliver higher speeds with the same amount of pressure delivered over a longer barrel burn time with slightly slower burning powders like AA9 for example. Case capacity limits the amount of powder, but burn rates can alter the pressure curves quite a bit. I've recently loaded a batch of 115 gr bullets with safe charges of AA9 but haven't had a chance to chronograph the loads yet. I do expect higher than normal velocity, but no increase in pressure signs.

I agree, Lil'Gun fills to case, burns slow enough for good velocities, works the action but does not over work it. To me it seems to burn cool, measures easily and works.

Word of warning,  Lil'Gun should be kept to 45,000 PSI or less, use in higher pressure cartridges has lead to excessive flame temperatures,  enough to damage forcing cones.
David Milisock
Back to Top
Matt_X View Drop Down
Grunt
Grunt


Joined: Nov 10 2020
Location: Phila, Penn
Status: Offline
Points: 573
Post Options Post Options   Thanks (0) Thanks(0)   Quote Matt_X Quote  Post ReplyReply Direct Link To This Post Posted: May 21 2022 at 1:10pm
Originally posted by Sawbones Sawbones wrote:

Evansville Cartridge Company 1944 and Lake City 1952 all measured 1.665 +/- 0.002" all chambering beautifully w/o 1 jam.  Likewise the off-the-shelf Sellier & Bellot ammo OALs measuring identically to that of the milsurp.


Observation: 
SAAMI recommended OAL for the 30 carbine cartridge is 1.680".
Milsurp  obviously much shorter at 1.665" +/- 0.002".


Remington Arms Co.  Product Drawing C-30124   Feb 7, 1942
1.680" maximum, 1.660 ? " minimum 
 In pencil next to that looks like 1.679" ? max and 1.637"? min.  Possibly these pencil notes are for production engineering??
Drawing is in Riesch 8th edition, p188.  Unfortunately digitized printing makes it near impossible to read under10x magnification.

Kuhnhausen in figure 30 (p.44) provides the overall length as 1.680 max, but 1.625 min. for commercial.
In note 1 he states the 1.625 minumum accounts for various bullet lengths, but it would be a 1.678" minumum "based on a seated 200955 standard military bullet." 
Phrased that way, I was not sure this 1.678" is actually on a the 1942 and 1943 drawings.

Ruth's War Waby! vol II  has a copy of Ordnance drawing B200954 for Ball Cartridge, revision 5 (10-3-1944).
Overall length is 1.68 with a tolerance of -.02"
By my math that's a minimum on inspection of 1.66"
  Smile
 
 


Edited by Matt_X - May 21 2022 at 1:39pm
Back to Top
floydthecat View Drop Down
Hard Corps
Hard Corps


Joined: Oct 13 2016
Location: Mississippi
Status: Offline
Points: 1655
Post Options Post Options   Thanks (0) Thanks(0)   Quote floydthecat Quote  Post ReplyReply Direct Link To This Post Posted: May 21 2022 at 1:28pm
I do shoot 85-grain Mauser bullets seated to around 1.625. Hornady has a published load for it. 
Back to Top
 Post Reply Post Reply Page  12>

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.078 seconds.