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JRDANIELS
August 7, 2009, 07:22 PM
Who makes a good off the shelf AR-15 for service rifle competition? I have found several standard A2 rifles that look nice but I have read that 1:7 twist is most common for service rifle and the rifles I have found are mostly 1:8 or 1:9 twist. I really like the DPMS Panther DCM (1:8 twist) and DPMS Classic (1:9 twist). The The club where I will be shooting at shoots everything at 100 yards but I think they use a reduced size target to mirror the differant ranges of a service rifle match. I would like to shoot a 68 or 69 gr HPBT. I thought the 1:8 would work well but I hear I need 1:7 twist? A little confused. Help!! Thanks

Citizen Carrier
August 7, 2009, 11:50 PM
I bought a DPMS Panther DCM-legal (or CMP-legal) AR15 about a month ago for this same reason.

Rock River Arms probably makes the best off the shelf one out there, but I wouldn't feel under-armed with a Bushmaster CMP-legal or Armalite National Match model either. Might look into semi-custom or custom makers like Fulton Armory as well.

The 1:8 rate of twist should be fine. I'm going to load 75 grainers in mine once I re-establish a loading bench. The thing about the DPMS Panther model you are considering is that it doesn't come with a match trigger. You can amble along with the factory trigger for awhile if you use a high grip and your entire trigger finger (rather than just the pad or first knuckle) to squeeze the heavier trigger smoothly, but you'll eventually want to upgrade. Aside from a sling and plenty of 20 round magazines, a match trigger is one of the first things I'd buy.

Indeed, I'm at Camp Perry right now and am seriously thinking about picking up a Giesselle trigger tomorrow at their booth. If I chicken out at the cost, I'll at least get a Rock River match trigger to install...

4EVERM-14
August 9, 2009, 08:16 AM
Twist rate choice can be a personal thing. Some guys swear by one or the other. For bullets through 75gr. even a 1/9 twist can outshoot most riflemen's abilities at short range. The 1/8 and 1/7 twists are needed for the 80 and 90 grain slugs. Keep in mind that today 100 yards may be your longest range but tomorrow a chance to shoot 300 and 600 yards may appear and infect you with the need to keep doing it. Let your conscience be your guide.

Citizen Carrier- Get the Giesselle trigger. You won't be disappointed.

darkgael
August 9, 2009, 09:13 AM
Off the shelf....when I wanted one, I bought a Colt Match Target HBar. I have never regretted the decision. Out of the box it was magically accurate. I installed a national match hooded rear and added some weight to bring it up to 12lbs but otherwise left it stock. One of these days I'll float the barrel.
The one that I have has a 1-8" twist. I generally load the Sierra 77 grain MatchKing HPBT.
Pete

zoomie
August 9, 2009, 09:21 AM
http://www.whiteoakarmament.com/complete_uppers.htm

shooterer
August 9, 2009, 01:13 PM
Most Highpower shooters that are not shooting custom WOA start with stock RRA.

The top HP shooters in the world hang out here. www.nationalmatch.us.

Jim

boltgun71
August 10, 2009, 04:59 AM
I personally use and would highly recommend a Rock River Arms National Match AR-15. I would also suggest getting the 1/4MOA adjustable sights since you will be using it a-lot for reduced 100yd courses of fire.

emcon5
August 10, 2009, 09:49 AM
Colt Match Target HBar
As you noted the biggest problem for the Colt rifles is the barrel is not floated, something that is pretty important for a service rifle.

1:8 twist works fine for 80 gr Sierra matchkings.

I have an Armalite NM uppper. It comes with a floated barrel and NM sights, and has a decent stainless steel barrel. It is an excellent starting point for Service rifle, because honestly when you are getting started you can't shoot well enough to make the best use of a Krieger barrel anyway. Even so, it is capable of shooting High Master with the stock barrel, I have a Leg medal around here somewhere I earned with mine.
http://www.armalite.com/ItemForm.aspx?item=15A2NM&ReturnUrl=Categories.aspx?Category=8e8e5de6-5022-483e-812b-822e58014822

The least expensive way to do it is probably to get a stripped lower, and assemble it with the trigger of your choice (I like Jewell) and buy a complete upper.

Here is Armalites NM upper:
http://www.armalite.com/ItemForm.aspx?item=U15A2BNM-2&Category=bce7fa68-373e-4afc-b00e-63fe2c75d131

johnwilliamson062
August 10, 2009, 10:42 AM
"Service Rifle" is a CMP sub class correct?
I believe the CMP targets are all designed so the bulls eye is the width of the front sight at whatever range you are shooting, so the 100 yd would probably be a scaled down 1000 yard target already.

There are not many shooters at my local club who I think get much more out of their high dollar ARs than they would out of a CMP Garand rifle with NM sights.

emcon5
August 10, 2009, 12:52 PM
"Service Rifle" is a CMP sub class correct?It is an NRA Highpower subclass, open to M1, M1A, and AR15 rifles. The AR needs to be an A1 or A2 (ie, have a carry handle) with a 20" barrel, and look externally like a M16A2. The most important thing for an AR is a float tube under the handguards, so when you sling up in prone position, the pressure from the tight sling is on the float tube rather than the barrel.

The full course of fire at my local club is 20 rounds slow fire, standing unsupported with 2 sighters, 10 rounds standing to sitting rapid, with 2 sighters, 10 rounds standing to prone rapid, with 2 sighters, and 10 rounds prone slow fire, with 2 sighters. The rapid stages have a reload, with the first magazine loaded with 2 rounds, and the second with 8 rounds. The slow fire stages, and sighters for the rapids, the target is pulled and marked/scored between shots. For comparison, the 600 yard target used for prone slow fire has a 12" 10 ring, and a 6" X ring. The 200 yard reduced version of the same target has a 3.79" 10 ring, and a 1.79" X ring, and the 100 yard version has 1.75" 10 ring, and a .75" X ring

The full course of fire, standing and sitting are shot at 200 yards, prone rapid at 300 yards, and prone slow at 600 yards, but there are reduced/scaled down targets for shorter ranges. The local ranges only shoot at 200 yards.

The aiming black on the targets is ~6 MOA. The full dimensions of the targets are available in the NRA rule book here:
http://www.nrahq.org/compete/RuleBooks/HPR/hpr-w04.pdf

Mike40-11
August 10, 2009, 09:16 PM
Speaking of Camp Perry and Rock River.... I just spent most of last week down there for the CMP matches. I tried really hard to avoid it, but somehow an RRA National Match A4 followed me home.

Honestly, I didn't want to. Really. But Rock River was running a special at Perry. 900 bucks. 1:8 stainless match barrel, 2 stage trigger and 1/4 minute NM sights. What could I do? Oddly enough, they sold a LOT of them.

emcon5
August 10, 2009, 10:01 PM
Honestly, I didn't want to. Really. But Rock River was running a special at Perry. 900 bucks. 1:8 stainless match barrel, 2 stage trigger and 1/4 minute NM sights. Wow, that is a smoking deal.

What could I do? Oddly enough, they sold a LOT of them.I am sure they did. It will be interesting to see if any show up on Gunbroker in the next few days.

Casimer
August 10, 2009, 10:36 PM
You'll be fine w/ a 1:8. Plenty of people shoot a 1:8 successfully on the 600yd courses, and at reduced ranges. At the XTC service rifle matches that I shoot, the RRA NM's A2's are the most common entry-level service rifles. The White Oaks upper is a very popular upgrade from this set-up.

And I think that your bullet weight choice is appropriate for 100yds - but I'd advise at least a 75gr at longer distances.

If you haven't visited nationalmatch.us, you should join-up.



Where have you been told that a 1:7 is necessary?

The The club where I will be shooting at shoots everything at 100 yards but I think they use a reduced size target to mirror the differant ranges of a service rifle match.

Yes, they're probably using reduced targets. There's a standardized set of reduced range NMC targets that are used for 300, 200, and 100yd matches. Otherwise the full-range targets are huge. You'd definately notice the difference.

Citizen Carrier
August 11, 2009, 10:50 AM
Zediker's "Competitive AR15, The Mouse that Roared" has him writing to get a 1:7, and certainly not a 1:9.

But perhaps this is an older printing before 1:8s were available?

emcon5
August 11, 2009, 01:07 PM
Zediker's "Competitive AR15, The Mouse that Roared" has him writing to get a 1:7, and certainly not a 1:9.

But perhaps this is an older printing before 1:8s were available?

I suspect what he is talking about in 1:7 is Jack Krieger's excellent barrels, which are really 1:7.7, not that far from 1:8.
http://www.kriegerbarrels.com/DCM__AR_15-c1246-wp3394.htm

According to Jack, his 1:7.7 is good up to 80 grains, and 1:9 is good up to 69 grains. Krieger has been the gold standard for service rifle barrels for a long time, I don't think that has changed.

Frank White at Compass Lake Engineering (http://www.compasslake.com/service.htm) uses Krieger 1:7.7 blanks on his high end rifles, as does Clint at Fulton Armory (http://www.fulton-armory.com/FAR15NM.htm). It looks like White Oak (http://www.whiteoakprecision.com/pricing-products.htm) uses Krieger on their high end uppers as well.

The old joke on the 1:9 is that it is "one size fits none", too fast of a twist for the light bullets, and too slow for the better high BC heavy ones.

For what it is worth, I haven't found that to be the case with my 1:9 Colt barrel. It really likes Hornady 75 grain AMAX bullets, I haven't tried the 77 SMK in it. It also shoots the 52 grain SMKs very well though. That particular barrel would be fine for reduced course Highpower matches, and workable for full course, but I would be giving up a little ballisticly with the Hornady 75 AMAX over the 80 SMK at 600 yards. Then again, maybe not, Hornady claims a higher BC (.435) for the AMAX than Sierra does for the 80 SMK (.420 at best, dropping at the bullet slows)

I may have got lucky though, I have heard of people trying the 75 AMAX in a 1:9 with horrible accuracy.

I have shot full course with My 1:8 Armalite upper, and it shoots the 80 gr SMKs just fine.

kbear
August 12, 2009, 01:16 AM
The rules for NRA HP Rifle have changed this year. You no longer start in the standing position for either rapid fire sitting or rapid fire prone. You now start in position but the magazine has to be on the ground.

In CMP it is still stand to sitting/prone but you start with the bolt closed on an empty chamber with the magazine in the rifle.

There is now a big difference between the NRA and CMP rules.

emcon5
August 13, 2009, 10:29 PM
The rules for NRA HP Rifle have changed this year. You no longer start in the standing position for either rapid fire sitting or rapid fire prone. You now start in position but the magazine has to be on the ground.

Really? I haven't competed for a couple years.

Why did they change it? It wasn't all that difficult. Even starting from standing and really pacing myself I have never come close to running out of time sitting or prone.

shooterer
August 14, 2009, 07:54 AM
Emcon5,

For safety reasons.:cool:They claimed that other shooters were being swept with muzzles on the way down.:eek:. Some say it was to keep the older good shooters shooting.:rolleyes:

Jim

kbear
August 14, 2009, 08:34 PM
The worst part is having NRA rules and CMP rules different. The nice part about the new NRA rules is that you can get a really good NPA.