Load for new Armalite NM AR-15?

[Blackcloud6]

I bought a new Armamlite AR-15 National Match rifle this weekend. It has a 1 in 8 twist stailness Lothar-Walther barrel.

I have a match on 15 August and would ike to use it.

My club Highpower matches are fired using the reduced targets for a 100 yard range.

What would be a good load for this match that I could work up in the next week and half?

Powders I have on have are WCC 846, WCC 844 and IMR 4895, all surplus.

I have some loads already made using 62 grain surplus green tips and IMR 4895 (I can't remember the weight right now).

Also, the manual tells me to do a 200 round break-in (I never much believed in this but...) so would it be ok to use the surplus loads I already have to do this? it seems a waste to use match components just to burn off 200 rounds. (Anyone use a boresnake for break-ins? I don't like jamming roads down my rifles)


Thanks.

 

[Kamicosmos]

I used a bore snake on my AR during break in, seemed to be just fine, but I don't have a chrome lined barrel.

I would imagine that one of your existing loads should work out okay, but as you probably already know, each rifle is different, and this particular rifle may decide it likes some component you don't have yet.

I use Varget and Nosler CT 55 grain bullets in my Varminter, which has a 24" barrel and 1 in 9 twist. It shoots .5 inch groups with that load.

 

[Khornet]

With mine

a DPMS DCM rifle, I use 55 gr FMJ bullets and IMR 4895 25.0-25.4 grains with very good accuracy. I've also loaded this with 748 and gotten good results, can't remeber the charge.

I just loaded up a test of 20 rd IMR 4895/23.5 gr/Hornady 68 gr BTHP match bullet. We'll see.

 

[wanderinwalker]

Sadly, I am too late for your match, but here is something that may be of help.

A good short-range (200-300) load, which even works nicely at 100 yards, is a 69gr Sierra Matchking or Nosler J4 loaded over 24.5gr of Varget in a Winchester or Lake City case ignited by whatever primer floats your boat (CCI, Winchester or Remington). You could try 52gr Hornady's as well, which are excellent IMO. With the light loads you'll likely use at these ranges, W748 is a good powder, but I won't use it under heavy bullets. I HAVE experienced pierced primers with 748 and WSR primers. NO MORE!!

My current favorite for shooting at 200 and 300 yards in my Armalite NM M-15 is a 77gr Nosler J4, healthy dose of H4895, touched off by a WSR primer, loaded into a LC case. At 600 yards this combo will work if the wind is favorable, but I prefer to load 80s. Actually, I have yet to work up a load with H4895 and the 80gr Nosler J4s for long-line shooting. So far I have used Varget at matches that have gone to 600, with excellent results.

 

[Steve Smith]

Yes, avoid WSR primers wtih heavy bullets. You're just asking for pierced primers. As WW said, a god 200-300 load works well for 100 too, but you can use 52's at 100 with great success and less recoil. A good barrel and bullet combo will not be powder sensitive in most cases, but you could use a slightly warmish load with a Rem 7 1/2 primer and she oughtta shoot knots.

 

[Blackcloud6]

Thanks for all the help guys.

So it seems that a lighter bullet load may be the way to go for the 100 yard match.

I'll consider the 52 gr. Hornady's. Now I have two jugs of surplus WCC 844. Would this be good to push the Hornady's? Or should I by a commerical powder like Varget?

I fired Saturday's match usinf Winchester white box 55 gr stuff. I didin't think it performed well enough fo match ammo. I also think there were a few fliers as twice I had a miss that was way off to the right and I called the shot in the black. I usually can tell when I cause a round to go way off.

I would like to tune some ammo to this gun so there are no excuses

 

[Jim Watson]

Buy some Sierra bullets,
Call Sierra.
They will tell you the starting and maximum loads you could read in a manual, but they will also recommend a target load based on their feedback from customers.
I have done good shooting with their recommendation. I don't have it at hand but it was for a 52 gr MK and a medium load of 748.
I loaded some .30-06 with 175 MKs according to a very experienced friend's data and it shoots like a dream.
Don't get carried away with load development. You can plink away a lot of a good barrel's service life trying to save an eighth of an inch.

 

[Blackcloud6]

Jim:

Thanks. Calling Sierra is a good idea.

I was wondering about using barrel life to "work up the load." I'd rather use it for practice and matches.

Fred