I was thinking about doing a 6.5 creedmoor build and I was looking for any suggestions on what would be best suited for PRS. For a trigger I was either looking at either Geiselle or Timney, Magpul PRS stock and a Criterion Barrel. Just undecided as to more of the internals. What's the best BCG to go with along with buffer and spring? What kind of gas system should I run? Any input on this would be amazing!
- Thread starter James.Walton3
- Start date
There’s lots of info out here in threads on 6.5CM builds... there’s other guys more experienced than myself that may chime in here, but here’s my input:
- Run a Rifle +2” gas system, shortest I would go is Rifle Length.
- An adjustable gas block is recommended. I use SLR.
- A JP SCS and the weight/spring packs will help you smooth it all out for the best operation.
- I like Toolcraft BCG or Rubber City Armory. Some also like JP where you can get LMOS or VMOS to really tune the action.
- I use and like Larue MBT triggers (now only $87) and Elftman triggers. I have one of each in my 6.5 rifles.
- you’ll get lots of input on barrels. A quality precision barrel turned out by a custom shop isn’t as out of reach as you may think, so don’t limit yourself. As far as factory barrels, Criterion barrels are good, I have one in 308 and it shoots well. I also have Larue and Faxon in 6.5 both of which shoot very well, but that’s where my experience ends with large frame barrels.
Good luck.
- Run a Rifle +2” gas system, shortest I would go is Rifle Length.
- An adjustable gas block is recommended. I use SLR.
- A JP SCS and the weight/spring packs will help you smooth it all out for the best operation.
- I like Toolcraft BCG or Rubber City Armory. Some also like JP where you can get LMOS or VMOS to really tune the action.
- I use and like Larue MBT triggers (now only $87) and Elftman triggers. I have one of each in my 6.5 rifles.
- you’ll get lots of input on barrels. A quality precision barrel turned out by a custom shop isn’t as out of reach as you may think, so don’t limit yourself. As far as factory barrels, Criterion barrels are good, I have one in 308 and it shoots well. I also have Larue and Faxon in 6.5 both of which shoot very well, but that’s where my experience ends with large frame barrels.
Good luck.
I built a 6.5mm Creedmoor Large Frame DPMS MSR AR, LR-308, AR-10... (what the hell do we call these things now?)
For the trigger, I used a Geissele Hi-Speed National Match with the Match spring. It's a two stage and it comes with three springs, so you can choose your weight. The first stage pull distance, second stage break, and overtravel are tunable with set screws. It's the most adjustable trigger I've ever seen.
I used the MagPul PRS GEN3 stock with a standard length rifle buffer tube. It comes with an adapter for an M4 carbine stock too, but just stick with the rifle buffer tube and you won't have to screw with a castle nut. You'll want the GEN3 because the comb is set back far enough to clear the extra length of the AR-10 charging handle.
I wanted the option to be able to have a suppressor, so I bought JP Rifles internals for adjustable internal mass. I went with the JP Rifles Variable Mass Operating System bolt carrier with the JP Rifles High Pressure EnhancedBolt. For the buffer, I used a JP Rifles Silent Capture Spring Heavy Version. I bought four of the steel weights and the spring pack and while I wait for my can, I am running steel weights and a lighter spring. When the can is out of ATF jail, I will put on the tungsten weights and possibly increase the spring weight.
I have a Proof Research 22" barrel that is rifle + 2" and comes with an appropriate length tube. I use a JP Adjustable Gas Block on it.
Muzzle device is the standard .308 flash hider while I wait for the can and mount.
I have topped it off with Burris XTR II 4-20x50 H591 scope with the AR-PEPR mount.
You can use whatever you want for the upper lower, handguard, grips, LPK, etc... I used a match M5 set from Aero Precision with their parts kits.
Now, if you like your handguards to cover your gas blocks, just be aware that the rifle + 2" will stick out a bit from most 15" rails.
I used a XXL (17") JP Rifles Handguard which covers the gas block nicely but doesn't occlude any of the adjustment screws.
This thing is a beast and weighs at least 14 pounds. I don't shoot it offhand much, best accuracy is from prone on a mat on an Atlas bipod.
It is sort of like the JP LRP-07 but with a better barrel and trigger, minus the side charging, and $1000 less.
For the trigger, I used a Geissele Hi-Speed National Match with the Match spring. It's a two stage and it comes with three springs, so you can choose your weight. The first stage pull distance, second stage break, and overtravel are tunable with set screws. It's the most adjustable trigger I've ever seen.
I used the MagPul PRS GEN3 stock with a standard length rifle buffer tube. It comes with an adapter for an M4 carbine stock too, but just stick with the rifle buffer tube and you won't have to screw with a castle nut. You'll want the GEN3 because the comb is set back far enough to clear the extra length of the AR-10 charging handle.
I wanted the option to be able to have a suppressor, so I bought JP Rifles internals for adjustable internal mass. I went with the JP Rifles Variable Mass Operating System bolt carrier with the JP Rifles High Pressure EnhancedBolt. For the buffer, I used a JP Rifles Silent Capture Spring Heavy Version. I bought four of the steel weights and the spring pack and while I wait for my can, I am running steel weights and a lighter spring. When the can is out of ATF jail, I will put on the tungsten weights and possibly increase the spring weight.
I have a Proof Research 22" barrel that is rifle + 2" and comes with an appropriate length tube. I use a JP Adjustable Gas Block on it.
Muzzle device is the standard .308 flash hider while I wait for the can and mount.
I have topped it off with Burris XTR II 4-20x50 H591 scope with the AR-PEPR mount.
You can use whatever you want for the upper lower, handguard, grips, LPK, etc... I used a match M5 set from Aero Precision with their parts kits.
Now, if you like your handguards to cover your gas blocks, just be aware that the rifle + 2" will stick out a bit from most 15" rails.
I used a XXL (17") JP Rifles Handguard which covers the gas block nicely but doesn't occlude any of the adjustment screws.
This thing is a beast and weighs at least 14 pounds. I don't shoot it offhand much, best accuracy is from prone on a mat on an Atlas bipod.
It is sort of like the JP LRP-07 but with a better barrel and trigger, minus the side charging, and $1000 less.
I chose a jp precision barrel and all their internals and moving parts. Trigger tech trigger ,aero upper and lower with a prs stock to help balance the gun. I don’t think your gonna get a light weight gas gun in 6.5 creedmoor because you need a longer barrel and gas tube. This was my last load development group. 3 shots at 200 yards. No they don’t all group this well but never bad and functions flawless.
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I just completed an AR10 6.5 build. I'd go with a 20" Proof Research barrel. With the 6.5 you need the rifle length plus 2 gas system. A HP bolt and adjustable gas block is a must. I'd go with the JP Low Mass Bolt Carrier & HP bolt. I also used their silent capture spring. I used the Ascend Armory match reciever, magpul stock, fortis rail. I used the Draco's barrel. It shoots but I'm not sure I'd recommend it or not. Lets say I'm neutral on that recommendation. Maybe after I get more rounds down range. I just now got it all tuned and good glass installed. Haven't gotten a chance to do much with it since. 
I’m shooting a Faxon 20” fluted. Accuracy has been good with a variety of factory ammo. I’m using a Rubber City Armory HP bolt/carrier, velocity 3 lb trigger, SLR adj GB.
Prime 130, Hornady 147s and Hornady Black 140s all shoot around 3/4 moa. Hornady 120 ELD-M are around 1.25 moa. The barrel has rifle length gas and all cycle great with standard AR10 spring and buffer.
A buddy of mine has the same barrel with very similar results with Winchester match 140s. We have taken them out to 300 yds with consistent sub moa peeformance.
The velocities for mine are below.
2622 FPS avg - Black 140s
2621 FPS avg - 147 ELD-M
2850 FPS avg - PRIME 130
On a 96 degree day with high humidity at sea level.
Prime 130, Hornady 147s and Hornady Black 140s all shoot around 3/4 moa. Hornady 120 ELD-M are around 1.25 moa. The barrel has rifle length gas and all cycle great with standard AR10 spring and buffer.
A buddy of mine has the same barrel with very similar results with Winchester match 140s. We have taken them out to 300 yds with consistent sub moa peeformance.
The velocities for mine are below.
2622 FPS avg - Black 140s
2621 FPS avg - 147 ELD-M
2850 FPS avg - PRIME 130
On a 96 degree day with high humidity at sea level.
Depending on what you call "lightweight ", you can actually build a light 6.5 CM. The one in the following link is 6.5# and I'm the builder/owner. I'm not a PRS shooter, not yet anyway, and I'm not certain you would want to go this light for a competition gun, but I sure would not want a 14# gun either. Anyway, take a look, it's easy to add weight here and there if you need more.
https://www.snipershide.com/shooting/threads/lightweight-2a-arms-xanthos-6-5-cm-build.6877340/
https://www.snipershide.com/shooting/threads/lightweight-2a-arms-xanthos-6-5-cm-build.6877340/
Search out padoms posts on a 6.5 build.
I've got a 24" 6.5 Creedmoor with rifle gas and no problems. It's not over gassed (Hornady box ammo) and runs smooth.
I've heard of some +2" gas systems causing short stroking.
Always get an adjustable gas system but I wouldn't go +2" unless my barrel is 24" long or longer and I don't feel bad about rifle gas on my 24".
I've heard of some +2" gas systems causing short stroking.
Always get an adjustable gas system but I wouldn't go +2" unless my barrel is 24" long or longer and I don't feel bad about rifle gas on my 24".
For optimal adjustability you want:
-JP SCS with the differebt weighted springs.
-an SLR Rifleworks 15 position gas block
- for bolt and carrier, jp makes LMOS that is good and a weighted system for adjustability amd use in suppressed rifles.
-JP SCS with the differebt weighted springs.
-an SLR Rifleworks 15 position gas block
- for bolt and carrier, jp makes LMOS that is good and a weighted system for adjustability amd use in suppressed rifles.
I built a 6.5cm Mega Maten MKM. Used a JP 22" barrel with the XL gas system, SLR gas block, JP VMOS bcg and SCS buffer/spring. Adjustable to no end, but I plan on running suppressed as soon as the Ultra 7 gets out of ATF jail. Use a Geissele hi-speed NM trigger & Magpul PRS stock on the lower. Also switched to the Geissele super charging handle ... butter smooth!
Also picked up a 308 rifle length upper on here with a Proof barrel. Both work VERY well.
Also picked up a 308 rifle length upper on here with a Proof barrel. Both work VERY well.
Never seen a properly made 6.5cm +2 gas barrel short stroke to date and Ive had many through my hands. First 3 rifle gas barrels in 6.5cm I had all had nasty case head damage and some blown primers no matter what gas was tuned to. When going +2 gas you need the proper gas port size. I would never go back to rifle gas again. I wouldnt go 22" or longer without +2. There a reason everyone is making their 6.5cm barrels with +2 gas length....With +2 gas system length, once gas block and buffer are properly tuned brass looks like it was fired in a bolt gun, super soft recoil and if the barrel is capable, excellent accuracy.
FULLY agree ...
I had a 260 GAP10 G2 with rifle length gas, SLR gas block and only a 20" barrel that abused brass when shooting with the can installed. I even upped the weight on the buffer with tungsten to a touch over 10ozs and it would still make light ejector swipes on about half the brass. Only thing that got rid of ejector swipes was taking the can off and running a brake.
This new 22" barrel with the +2 gas system has me itching to run it with the TBAC can, both to see the difference in velocity and see what happens to the brass when I get it tuned for the can. I still have the OpsInc can but it requires a shoulder on the barrel and 11/16-24 threads, so that ain't happening on these uppers.
Are you running with a silencer? That is the BIG contributor to brass issues with 6.5cm/260 gas guns.
I built mine with adjustable gas block and heavy BCG/SCS components and a TB CB brake to eventually screw on an Ultra 7 or 9 can.
While I wait for that, I think I'm going to start playing around with the weights and springs to see what works best unsuppressed.
I have tried the heaviest and the lightest combinations of weights and springs and there's a definitely a difference.
I adjusted the gas block with each setting and I prefer the heavy, slower BCG movement even unsuppressed.
While I wait for that, I think I'm going to start playing around with the weights and springs to see what works best unsuppressed.
I have tried the heaviest and the lightest combinations of weights and springs and there's a definitely a difference.
I adjusted the gas block with each setting and I prefer the heavy, slower BCG movement even unsuppressed.
Key here with getting all these components dialed in correctly is dwell time. Your trying to keep that bolt closed as long as possible so pressures can subside and the BCG can easily extract the brass. When you dont have it tuned correctly your BCG is ripping that brass out of the chamber before pressures subside. You will have to tune everything again once you throw a can on there.
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Not everyone is making +2" gas 6.5 Creedmoor barrels.
Of course running a can is a good reason for +2" because it's going to increase dwell.
The only thing bad about some of my brass is neck dings but that's because I haven't bothered to do fuzzy Velcro on my case deflector.
If I was reloading really hot with a semi-auto unfriendly pressure curve, I bet mine could beat up brass too.
As it is I'm getting about 2,750 fps with 140 grain ELD-M and no problems with a rifle length gas 24" Criterion barrel (and adjustable gas block with plenty of adjustment left on both sides).
I think I understand what you're trying to say when you mention "lock time" but lock time is actually related to triggers, not when the bolt unlocks.
Everyone making this choice should try to understand exactly what they are getting, not just compiling a list of every feature they have ever heard of.
Of course running a can is a good reason for +2" because it's going to increase dwell.
The only thing bad about some of my brass is neck dings but that's because I haven't bothered to do fuzzy Velcro on my case deflector.
If I was reloading really hot with a semi-auto unfriendly pressure curve, I bet mine could beat up brass too.
As it is I'm getting about 2,750 fps with 140 grain ELD-M and no problems with a rifle length gas 24" Criterion barrel (and adjustable gas block with plenty of adjustment left on both sides).
I think I understand what you're trying to say when you mention "lock time" but lock time is actually related to triggers, not when the bolt unlocks.
Everyone making this choice should try to understand exactly what they are getting, not just compiling a list of every feature they have ever heard of.
Fixed. Dwell time
Just to name a few
JP
Rainier
Proof
Odin Works
Patriot Valley
Shoot what you want, glad it works for you. My sample size is much larger than most and I shoot 99% suppressed and would never waste money on rifle gas 6.5cm again.
Just to name a few
JP
Rainier
Proof
Odin Works
Patriot Valley
Shoot what you want, glad it works for you. My sample size is much larger than most and I shoot 99% suppressed and would never waste money on rifle gas 6.5cm again.
My buddy at Prometheus arms is building a 6.5 for a friend that I’m pretty excited to test out.
Custom receiver set
JP high pressure bolt
Custom carrier done by Prometheus
Geissele sse trigger
SCS buffer system
SLR handgaurd
XLR stock
Custom cut bartlien barrel done by Prometheus
Custom receiver set
JP high pressure bolt
Custom carrier done by Prometheus
Geissele sse trigger
SCS buffer system
SLR handgaurd
XLR stock
Custom cut bartlien barrel done by Prometheus
Nice rig. But like you said jury is still out on the Dracos for me.
