Not a conversation about whether to do it or not, but rather a conversation of how to do it the best way possible. What would make the best gas gun setup for prs?
- Thread starter Hecouldgoalltheway
- Start date
Highly recommend a upper/handguard set where the handguard attaches directly to the upper receiver.
When shooting off various props the handguard gets loaded in different ways. If the handguard is attached to the barrel nut, there is potential to affect POI.
Admittedly this eliminates 90% of the options but if you want to compete seriously that shouldn’t concern you.
Do not skimp on the barrel. A gas gun is less forgiving to less than stellar heat treat than a bolt gun. I shot Craddock last year and the barrel I had at the finale is more accurate than my proof prefit bolt guns. A few other good companies too but don’t skimp.
When shooting off various props the handguard gets loaded in different ways. If the handguard is attached to the barrel nut, there is potential to affect POI.
Admittedly this eliminates 90% of the options but if you want to compete seriously that shouldn’t concern you.
Do not skimp on the barrel. A gas gun is less forgiving to less than stellar heat treat than a bolt gun. I shot Craddock last year and the barrel I had at the finale is more accurate than my proof prefit bolt guns. A few other good companies too but don’t skimp.
Admittedly I overdid it a little.
I was use a 26” Bartlien from Craddock, chambered in 6CM. If I could do it again, I would have used my 24” 6.5CM. The 6.5 just runs smoother in a gas gun. With the 6.5 I could get away with a LMOS carrier and still have great reliability. With 6CM I was using a VMOS carrier and overgassed slightly. Recoil ended up being lighter with 6.5.
I just specified the heaviest contour with the .936” gas block. 26” barrel with a maverick on the end was pretty unwieldy too.
Final rifle weight was around 21lbs. I had weights on handguard and weights in buttstock. Was great for matches like WAR rifles which was positional heavy. Not as necessary for finale.
I was use a 26” Bartlien from Craddock, chambered in 6CM. If I could do it again, I would have used my 24” 6.5CM. The 6.5 just runs smoother in a gas gun. With the 6.5 I could get away with a LMOS carrier and still have great reliability. With 6CM I was using a VMOS carrier and overgassed slightly. Recoil ended up being lighter with 6.5.
I just specified the heaviest contour with the .936” gas block. 26” barrel with a maverick on the end was pretty unwieldy too.
Final rifle weight was around 21lbs. I had weights on handguard and weights in buttstock. Was great for matches like WAR rifles which was positional heavy. Not as necessary for finale.
You're exactly who I hoped to run into when I asked this question, and I appreciate your help. What buttstock and handguard did you run, and would you change anything about them if you did it again? What about trigger?
Hmm. How much POI shift are you seeing with a barrel nut attached handguard between prone / bipod and off of a barricade? There can be a little poi shift with bolt guns too, and it has to do with recoil management and NPA typically. I always noticed a tiny bit of poi shift (1/4-1/2 moa tops between a sand bag and slung up in prone or sitting) in high power shooting with a sling in various positions but the sling also puts a lot of torque on the rifle, way more so than a bipod or barricade.
I put a 6.5 creed together recently for PRS but haven’t shot it yet. I went with a barrel nut attached handguard… now I’m curious.
Honestly not much. .1-.2 mil max. But you're also correct on POI shift due to position behind the gun which can potentially stack with variation from handguard. I'm not saying the handguard attached to the nut means you can't compete, just that if you're building from scratch you might as well remove a variable. Its probably not worth changing if you've already built it.
I've been making Long Range Precision Gassers for a long time now, and if all goes well I will also be competing in PRS this year with @FALex.
Some of the key points of putting together a large frame AR for competition have been touched on above, so I will only reiterate those points briefly.
Let's start with receiver options and then move from the muzzle to the rear.
(1) As stated above you don't want to run a conventional receiver set where the handguard attaches directly to the Barrel Nut due to the fact anytime you induce any stress on your handguard by bracing your rifle on a barricade or loading the bipod that force is going to transfer directly to the barrel.
So that basically leaves you with (3) options..
Seekins SP10
JP LRI-20
LaRue OBR or PredatAR,....I honestly don't recommend running these unless you already have one and are not planning on running a barrel with a gas system longer than Rifle length on the OBR or +1 on the PredatAR because a + 2 gas system will stick out too far past the handguard possibly causing other issues and the last thing you want to have is a exposed gas system in PRS.
You can purchase the Seekins and the JP as builder kits, but LaRue does not offer that and his receivers/handguards he uses for his ultimate uppers are cheap and just don't compare to the OBR or PredatAR, so that's why unless you already own one it's not worth purchasing just to modify.
I really like the flat bottom handguard style of the SP10 which also accommodates a Arca rail extremely well. The JP handguards are round but they also offer a solid ARCA rail attachment system.
(2) Pick a Muzzle Brake that provides significant recoil reduction, I personally recommend the American Precision Arms Gen 3 Little Bastard or area 419 Hellfire Match.
There are several good MB options these are just the two that I enjoy, whichever one you decide to run I would recommend putting a couple drops of blue loctite on the lock ring.
(3) The Barrel!, Heart and Soul or your Rifle. As stated above don't skimp on the barrel or go the light weight route.
You want a heavy barrel Contour and your barrel length either 22" or 24". I go with the M110 Contour on all my barrels. There are several good Smiths that can turn you a quality Barrel but these are the three that I recommend.
CLE, Craddock or Keystone.. Compass Lake is my go-to Paul Ross at CLE does phenomenal work.
I run Bartlein four groove blanks on all my rifles in the following configuration. I'm assuming you'll be running 6.5 CM or 6CM?
22"-24" Bartlein / 1-8 Twist / M110 Contour with +2 Gas System/ .875 gas block Journal step down to .850 to the muzzle / 5/8x24 Threads.
(4) Reliability is key if you can't finish you can't win, you want to run a Full Mass operating system with a minimum H2 Buffer with a reasonably stiff spring.
Moving through different stages of the competition you're not always going to have time to oil break things down and clean so your system needs to be able to run no matter how dirty it gets.
For the BCG I personally like the Lantac Enhanced Full Auto HP .308 BCG, with its oversized rear boss to prevent carrier tilt and directional gas port for a smoother rearward recoil impulse and 1lb 2oz weight. There are a few others that are great as well, RCA and JP Full Mass or Vmas BCG all work well.
For your gas system id recommend a Adjustable Gas Block, pick one that suits your needs just know they are all going to carbon lock at some point it's just the nature of the beast. Adjustable Gas Key on your BCG is also a great option.
Set your gas system for a 3 O'clock ejection pattern, you want to tune your gas so the that your BCG will lock back to the rear on the last round then add a little extra gas.
I run the JP H2 SCS and have never had an issue with reliability, but for a competition setup I'd probably look at a traditional buffer with a Tubbs Flate wire spring or a Slash setup.
Your choice for your fire control unit is also very important, again reliability is key but having a smooth trigger with a clean break is also vital. TriggerTech is my go-to now, for a competition trigger the Adaptive AR-10 is probably the best option for TriggerTech. Other than that Geissele, and LaRue MBT or solid options.
(5) The Ergonomics of your rifle plays a large part as well, pick a grip that properly fits your hand size. If you have large hands the Ergo Tactical Deluxe Grips are nice I prefer their zero angle vertical grip. I've just started running the MDT adjustable vertical grip and so far I like it, the LaRue A-Peg are nice for medium to small hand fit.
And lastly your choice for your Stock. This is extremely important for proper Length of Pull and Head placement / Eye Relief, proper eye relief can obviously be adjusted by your scope placement but you still want all of them play well with each other. You want something that is rock solid and fully adjustable, the MagPul PRS Gen3 or Seekins 10x or great options but again you have to find one that fits you.
Hope this helps a little..
Jake
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My friend competed at The GAP Grind this past year with a gas gun. Used a Knight’s vaporware in 6.5CM shooting factory 140SST loads. Only guy to clear the 500 yard movers and placed 3rd, I believe. His only comment was he needed to get out shooting more to do it again. Without looking at the standings I think he beat all the pros in gas gun except the one that took first.
Knight’s 6.5CM, Nightforce, PRS stock. Nothing magical.
Knight’s 6.5CM, Nightforce, PRS stock. Nothing magical.
Would recommend listening to anything @lennyo3034 has to say… he won the gas gun division last season.
A have two LRs that I built for long range shooting and to try my hand at PRS - a .243 and a .308. Both using Aero Precision enhanced receiver sets and 24" X-caliber barrels, fluted, in AR10 Heavy contour, and 15" handguards. Gas system on the .243 is rifle length and the .308 is rifle+2" with SLR adjustable gas blocks and 3 chamber brakes. The next replacement .243 barrel will be rifle+2".
The .243 runs a Magpul PRS Gen 2 stock with a stock LR rifle buffer filled with tungsten weights and a cut down AR15 rifle buffer spring. The .308 has a Magpul UBR Gen 2 stock running a home-fabricated stainless steel A5-length buffer with tungsten weights and a cut down AR15 rifle buffer spring. Both buffers are about 9 oz. BCGs are Aero Precision with RCA bolts. The combination of heavy buffers, light buffer springs, turned down gas, and muzzle brakes help to reduce felt recoil and the lighter buffer springs reduce the forward impulse of the BCG as the rifle chambers another round. The .243 has a Geissele SSA-E and the .308 runs an SSA trigger. Currently have a Vortex 24x PST 2 scope on the .243 and a 24x Arken atop the .308.
Both rifles weight around 14.5 lbs with optics and bipod and shoot 1/2 MOA at 100 using handloads. I'm not winning any awards at PRS (I blame that on being old and inflexible) but the rifles both shoot well - way better than I can employ them.
www.snipershide.com
The .243 runs a Magpul PRS Gen 2 stock with a stock LR rifle buffer filled with tungsten weights and a cut down AR15 rifle buffer spring. The .308 has a Magpul UBR Gen 2 stock running a home-fabricated stainless steel A5-length buffer with tungsten weights and a cut down AR15 rifle buffer spring. Both buffers are about 9 oz. BCGs are Aero Precision with RCA bolts. The combination of heavy buffers, light buffer springs, turned down gas, and muzzle brakes help to reduce felt recoil and the lighter buffer springs reduce the forward impulse of the BCG as the rifle chambers another round. The .243 has a Geissele SSA-E and the .308 runs an SSA trigger. Currently have a Vortex 24x PST 2 scope on the .243 and a 24x Arken atop the .308.
Both rifles weight around 14.5 lbs with optics and bipod and shoot 1/2 MOA at 100 using handloads. I'm not winning any awards at PRS (I blame that on being old and inflexible) but the rifles both shoot well - way better than I can employ them.
308 AR10 Build Info/Picture Thread
My lightweight hunting 2aArmament 308 build 2aArmament Xanthos receiver set 20” Rifle Gas ProofResearch 308 Barrel SmokeComposites CF HG SmokeComposites Pistol Grip SmokeComposites Fixed Rifle Length Stock 2aArmament Ti GB 2aArmament Ti RBCG 2aArmament Ti Pins V7 Small Bits NF 2.5-10 NXS in a...
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He shot great and had a good spotter and coach if I do say so myself. Though to be fair, the AMs had easier targets and coaching.
Obviously, @bigjake83 has the heart and soul, vis-a-vis, the system variable, in the equation down to a fine science. I would only add balance, try to get your rifle as well-balanced as you can.
The other variable in this "I wanna run a gas gun in competitions" equation is the fella running the bang stick. You may believe, or even know, that you can shoot a gas gun accurately. However (emphasis added), this does not translate to, "I can run a gas gun accurately during competitions." There is a very specific reason that 99% of competitors run bolt guns, and that reason is because the fundamentals between the two are less stringent for the bolt gun operators.
When running a bolt in a competition, the lack of reciprocating mass, means you can send a shot with, what may be a shitty cheek weld, or a not-so-good NPA. When you've got the added cycling concern with the gas guns, if you've got inconsistent cheek welds, or maybe your NPA just isn't where it needs to be, you're going to experience negative results.
Anyhow, I realize you were just asking about equipment, but I wanted to add a little bit of reality onto that mix, and that was not diving into the minutiae of this particular issue.
To sum it all up: get yourself a quality receiver set, a high quality barrel, make sure it's installed by a competent individual (I've been learning about this topic from @bigjake83. I was never really into building AR's, I just shoot the shit out of them), get an appropriate gas system, put a quality trigger, buttstock, etc...and get after it.
Best way to do it would be to buy something with the best resale possible so you can dump it when you realize running a large frame gas gun at a recoil management competition puts you at a huge disadvantage so doing so is basically retarded.
Or build an SPR and go shoot DMR matches instead which are way more fun than what PRS has become anyway.
Or build an SPR and go shoot DMR matches instead which are way more fun than what PRS has become anyway.
A lot of great advice already, so I'll throw my 2 cents in.
For me, a good ambi-bolt release is a must have. General match rule around here being to drop the bolt only once you're on target, it's great to drop the bolt with my trigger finger and keep my support hand where I need it. I find that I jam my finger into the BAD lever type that are in the trigger well, so integrated ambi on the receiver is great. For this I prefer my Seekins SP10/GAP-10 receivers with the lever. I also prefer them because of the semi-monolithic handguard and I can attach a weighted bag to the arca rail, which is one less thing to think about grabbing when moving on props.
Good balance and weight is also critical, you want to get positioned tight behind the gun, but if it's balanced properly it is much easier to get into proper and stable position.
Magazines choice is important, PMAGs work great, but I found with my 135 a-tip load they shoot best seated around 2.850" oal, which required KAC mags. Make sure your mags aren't the week point so you're not stuck trying to clear mag related jams on the clock.
For me, a good ambi-bolt release is a must have. General match rule around here being to drop the bolt only once you're on target, it's great to drop the bolt with my trigger finger and keep my support hand where I need it. I find that I jam my finger into the BAD lever type that are in the trigger well, so integrated ambi on the receiver is great. For this I prefer my Seekins SP10/GAP-10 receivers with the lever. I also prefer them because of the semi-monolithic handguard and I can attach a weighted bag to the arca rail, which is one less thing to think about grabbing when moving on props.
Good balance and weight is also critical, you want to get positioned tight behind the gun, but if it's balanced properly it is much easier to get into proper and stable position.
Magazines choice is important, PMAGs work great, but I found with my 135 a-tip load they shoot best seated around 2.850" oal, which required KAC mags. Make sure your mags aren't the week point so you're not stuck trying to clear mag related jams on the clock.
Ballistic Advantage premium 20” bull. Yeah, cheapo barrel, but I’ll take those groups!
You probably need a longer gas systems then you think. I shoot a 24in 22cm with a +2. Ill probably try a +3 or +4 on the next barrel. The +2 shoots pretty good, but I feel like I could get a softer shooting rifle that is easier on brass with a longer system.
Shot my match Saturday with my ar10. I had a set screw strip out on my jp gas block on Thursday before the match, and I couldn't fix it, so I basically shot it with about 4 times as much gas as I should have. Needless to say, I looked like a coal miner by the end of the day. There were moments of glory and stages with 0 hits. I had several other issues that day with my rifle, but they were all self inflicted. I have 2 weeks to work out the bugs before the April 1st match at K&M. I have a superlative arms bleed off gas block on the way, and that will fix most of my issues. I couldn't even recover my brass because it was throwing it about 30' away at 1 o'clock, and it was mostly trashed from the ejection, so I guess I didn't need it anyways. This is my configuration, but I had added about 4lbs of weight to the handguard. Had some 1,200y impacts in 20+ mph gusts, and had several stages where I lost rounds to malfunctions due to the absolute filth caused by my overgassed system. Believe it or not, that meopta scope that I bought used for $600 performed flawlessly. I was spotting impacts at ranges out to 1,200y with awful mirage and strong winds. Guys laying prone right next to me with scopes that were 5 times as much or more couldn't see them. Tracked flawlessly.
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I believe you were in my squad. That brass came out black!
I have the LF gasser itch as well. Current going the Aero Enhanced with Sgt of Arm rail.
@Hecouldgoalltheway
so, being seriously overgassed, was your bolt carrier, the back of the fat part, making contact with the buffer tube or the lower receiver upright? leave any impact marks?
I have a jp silent capture spring, so hopefully it kept it from any damage. I pulled it all apart and cleaned it up on Sunday and didn't see any damage.
Hey, I meant to ask you all day what chasis you were running. It was something I hadn't seen before, and your buttstock was something different too?
It was the AI ATX AICS. Been running it since December and loving it so far.
Did the set screw on your JP gas block get carbon locked? Do think the Superlative Arms will be better? I've seen AGB go down and starting to believe you'll have to treat them like barrels with a limited useful life.
No, it wasn't carbon locked. I lost the set screw that keeps the adjustment screw from moving. It must have been loose and worked itself out while firing last week. I had replacement screws and got one that threaded in just fine, but when I went to adjust it again on Thursday it wouldn't break loose and then the head stripped. The main adjustment screw was stuck wide open, but it wasn't moving, so I just ran it. I'm hoping the design on the superlative arms is just a little more durable. It also adjusts without tools (I think) which is a bonus. I pulled the JP off Sunday and checked it. The gas port in the barrel was about 80% blocked, but there wasn't much build up in the gb. I gave it an hour in the ultrasonic anyways with carbon remover, and it came out like new. I will fix it and use it somewhere else.
