L42A1 and L39A1 accuracy standards

[bombdoc]

Are we SURE that Ruag made the ammo (see thread 14, para 1) - or did they simply make the cases on contract for RG as others have done before. I don't mean NRA contracts or other commercial stuff but UK Military spec NATO Ball.

I'm not an ammo tech but hope Bombdoc and Ensci come in to clarify this. I just feel that it could cause all sorts of confusion, not to say problems, if we had RG 'made' ammo made somewhere else with no means of identifying it except for the notion that the case stamping was '.......not as deep'

Just me being a bit suspicious after years of knowing (sorry....., fumbling) my way around the ADAC system and how it works. And this isn't how it works in my opinion

Are you there Bombdoc?

This does seem strange.. I was not aware of RUAG assembing any L2A2 ball at that time, however RG was going through one of its (many) churns, so it is possible that some components would have been imported for some batches.. However the major turmoils in the RoFs did not occur until later..

There are a whole range of 7.62 ball rounds in the catalogue these days:

L2A2 9.33g bullet NRN41 FN/T propellent and VH2 primer
L2A5 9.33g bullet NCW SB 1500 propellent and VH2 primer
L44A1 9.33g bullet NCW SB 1500 propellent and Sinoxid primer
L46A1 9.32g bullet CBC 102 propellent and CBC primer - only used in link

...and again in 155gn:

L42A1 Sniper 10g bullet double base cut tubular propellent and VH2 primer
L42A2 Sniper 10g bullet RG4210 propellent and Sinoxid primer
L42A3 Sniper 10g bullet E1 propellent and Sinoxid primer

The L42A3 may be encountered as "Round 7.62mm Ball 155gn Competition" in trade packs.

and finally...

L52A1 Sniper 12g bullet Vit N150 and Sinoxid primer.

There have been a number of policy changes with RG 7.62 over the decades, and it is sometimes difficult to separate fact from fiction, even in the trade.. The use of the Black Spot and Green Spot seems to have varied as well. At one time, black spot was standard run ammunition with a high value of merit at testing whilst green spot was specially made from selected components and using dies in the first quarter of wear. This however has changed on a number of occasions.. RG at one time was capable of producing some very high quality 7.62, but this was in the 80s when the plant was relatively new and the production was stable. Latterly the factory was reorganised to switch over to 5.56 and standards were not as well maintained. The factory has recently been rebuilt, so hopefully standards should return!

[Brian Dick]

I have a couple of cases of Hirtenberger caliber .308 Winchester, 150 grain soft point that have RG 90 NATO headstamp marked cases that are Boxer primed. Not only is it extremely accurate fodder but the brass is excellent for reloading.

[brent65]

[QUOTE=cprher;351455]Muffett.2008,

The headstamp on the round is AFF 88. On the bandoleer is printed (from left to right) 50 7.62F4 AFF24 3 88 AUST/MK1 CP 1 (with an N below that) and 12/67 (which I first thought was a date code.

Keith[COLOR="black"]

---------- Post added at 08:06 AM ---------- Previous post was at 07:58 AM ----------


Mk1 refers to the bandoleer only not the ammo, Australian 7.62 was only ever mass produced/issued as L2a2 or later as F4 Ball

[muffett.2008]

Yeah, my bad. Meant F4, used to get three cases a year when I was with the Army Rifle Team, just for practice.........that's on top of what I used in service competitions.
Attachment 68399

[Strangely Brown]

5 years ago the NRA made a statement saying that if 155 Gr ammunition was going to be used in No.4 actions then those rifles would need to be reproofed to 20 Tons Psi.
All of us said it was a load of tosh and the NRA quietly withdrew back into it's shell.

At that time I was LERA's TR Captain and as a club we had decided that only 144/147 Gr ammunition was to be put through club rifles.
The problem starts here because at that time there wasn't a lot of choice of 144/147 Gr in the UK and the NRA had only L2A2 to offer, which from a TR perpective wasn't seen as that accurate.

Some research within the NRA indicated that when the Envoy/L39A1 etc were popular and winning the Queens final Raufoss ammunition was expensive.
Although when Raufoss first arrived in the UK it was immediately noted just how superior it was to the Radway Green offering of the period.

The answer was reloading, although in those days reloading was not as popular in the UK and seen here as an American thing!!

Well after some experimintation it would appear the most popular load at Bisley was a 150Gr SMK over 44 Gr's of N140 (or similiar). This came from a GB team member from that era.
This is the load I now use in all my No.4 based target rifles with v good results out to 900 yards.
At a 1000 yards my wind reading skills are not what they should be!

[Frederick303]

I believe 44 grains of N140 would be around 2,870 fps out of a 26 inch barrel.

That would run just about 1197 fps @ 900 yards, which is just about in the transonic region where accuracy might drop off. Sierra 9 degree boattail bullets are known for not being the best bullet in the transonic region. I have seen this with the Sierra 180 and 168 Sierra bullets with the 9 degree boattail bullets, in a heavy side wind their seem to go from good groups at 800 M to fan at 900 M

By 1000 yards the load would be around 1100 fps. Very much where the sierra bullets do not shine. Might not be you but the bullets, especially if you see adverse results in high wind.

I would suggest a bullet with a 6 to 7 degree boattail. The 180 gr sierra "old pattern" Matchking bullets with a 7 degree boattail handled 1000 yards just fine out of a M14, and they were just entering the transonic region at that range. Come to think of it, it might have been the velocity retention in that case.

[brent65]

I believe 44 grains of N140 would be around 2,870 fps out of a 26 inch barrel.

That would run just about 1197 fps @ 900 yards, which is just about in the transonic region where accuracy might drop off. Sierra 9 degree boattail bullets are known for not being the best bullet in the transonic region. I have seen this with the Sierra 180 and 168 Sierra bullets with the 9 degree boattail bullets, in a heavy side wind their seem to go from good groups at 800 M to fan at 900 M

By 1000 yards the load would be around 1100 fps. Very much where the sierra bullets do not shine. Might not be you but the bullets, especially if you see adverse results in high wind.

I would suggest a bullet with a 6 to 7 degree boattail. The 180 gr sierra "old pattern" Matchking bullets with a 7 degree boattail handled 1000 yards just fine out of a M14, and they were just entering the transonic region at that range. Come to think of it, it might have been the velocity retention in that case.

SMK's with a 9 degree BT are proven performers in the transonic zone for example the 155 palma, 173, 175, 190, 220 and 240gr bullets, all have 9 degree tapers and are all known for 1000yd performance and beyond.

The 180 SMK also had a 12 degree taper and the 168 has a 13 degree taper.

[Frederick303]

Opps that's right it was the 150, 168 and 180 new style that had the 13 degree boatail, not the 9

My mistake.

[cprher]

I shoot at Fort Meade, MD in the USA and the longest distance I have easy access to is 600 yards. I just ordered a box of 500 155 grain moly coated Sierra Palma bullets and will be using once fired military brass. I have a wide variety of powders available in quantity: IMR 4350, 4831SC, RE 15 and 19, Varget and a few others. Needless to say, I don't plan to hotrod this cartridge but rather keep the pressures well within the gun's acceptable limits.

How about you guys sharing your favorite loads that fit (or come close to fitting) my components of choice?

Keith

[smle addict]

I haven't made any handloads for my L39 yet, but here is a load I run through my DCRA No 4 in 7.62mm.

This load is listed in the Hornady manual, and has remained unchanged for editions #7 and #9.

42.0 grains of IMR4895 (run through powder trickler)
Hornandy 155 grain A-Max (moly coated)
CCI-BR-2 primers
Hornady custom cases (flashholes de-burred)
Bullet seated to 2.805 COL

Velocity listed is around 2550FPS. My chronograph died and I have yet to purchase a new one.

Velocity is mild and the load is accurate. Attached pic shows group that measured 1-1/8 inch (vertical) x 1-5/8 (lateral). That's 20 rounds fired at 100 yards.

No pressure indicators and cases easily eject.