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I have a similar conundrum, but my situation is with an R700PSS in .308 and an Armalite AR10 in .308. I've only shot one precision rifle series match and know my bolt gun isn’t ideal for the PRS 1000 yard + competition. Its .308 case capacity is limited and does hold enough powder to keep the bullet fully supersonic out past about 800 to may be 900 yards with reasonable pressures. Somewhere at those distances it starts going transonic depending on altitude, temperature, humidity and other factors. The AR10 gas gun gives up too much muzzle velocity to go as long as my.308 bolt gun. So, I’ve been kicking around the idea of re-barreling my AR10 with a 6.5 CM 24” barrel. I don’t want to use a 20” barrel. I’d give up a couple hundred ft/s in velocity with the shorter barrel and then I'd start having the same issues down range as the .308. Gas guns just don’t produce enough muzzle velocity to match bolt guns when you start reaching out to 1000 yards. At first re-barreling the AR10 to 6.5 CM looked pretty straight forward. All I needed was a barrel chambered in 6.5 CM and a barrel extension. The DPMS bolts and AR10 bolts are close enough they will work with either pattern barrel extension. Unless your unlucky enough to get an extension or bolt that’s on the far end of the tolerance limit and they aren’t compatible. Then all you’d need to do is get a new DMPS BCG to convert to DPMS pattern, right? The answer is gray. The big issue is the AR10 platform is not Milspec like the AR15 and you’re kinda doing your own R & D. This is where the story begins to get complicated. The available factory 6.5 CM ammo generates some high chamber pressures. JP has about as much info as there is on the big AR in 6.5 CM. They use an enhanced high pressure bolt to reduce pressure issues while tuning the gas gun. They use an improved ejector pin hole with modified ejector to mitigate case head extrusion and frequent brass shavings and a reduced diameter firing pin orifice that prevents primer material flow back. I’ve experienced some of these issues with an early DPMS upper in .308 that was way over gassed with factory ammo. Please keep us updated on your progress. I’m really interested in your project to see what the big AR style gas gun in 6.5 CM can do out to 1000 yards and beyond.

I ran the red dot first, but the dot was about the same size as the target at 100 yards. It's kind of a toss up. I went to a 1-4 power scope, but it added a lot of extra weight. I may go back to the dot.

Interesting question. I settled on 147g Hornady XTPs at about 1050 ft/s. My GMR-13 is getting sub 3 MOA hundred yard performance with that load. The problem with major power factor is keeping it supersonic out to 100 yards. The little 9mm BC is just not slippery enough to stay supersonic out to 100 yards. If you keep is subsonic, you don't have to worry about bullet upset as it goes trans-sonic before it get to 100 yards. JP hasn't tested with +P loads.

Update - After testing several brands of ammo with different bullet weights, I contacted JP. They said I may be the first to have accuracy issues with the GMR-13. They said to send it back. I shipped it back. After testing, JP engineer agreed with my findings. They are replacing the barrel. Should be getting it back next week. I received am email today from JP. They said my GMR-13 upper has a new super match barrel! JP tested it at 100 yards with Freedom Munitions 124g XTP. 5 shot group at 100 yards was 1.78 inches. They shipped it back today.Hopefully it will be here the first of next week. Here's the test target John Paul himself shot with my new barrel. The rest of the story. The PCC is awesome now! I'm not as good as John Paul, but I'm happy with my new barrel. I just shot for groups and didn't zero the red dot till after I ran 10 rounds over the Chrony. Here's the Chrony target from 50 yards. I called the flyers.

Heard some buzz at MO 3 gun championship this year about some 4 gun matches, but can't find anyone actually doing it. Anyone hear about a bolt gun long range stage in multi gun format?

I just ran the calculations through the JBM online ballistic calculator for the Hornady 6.5 Creedmoor, 140 grain A-max on a std day at an altitude of 850' with 41.5g of RE-17 @ 2700ft/s. The 6.5 CM easily stays above 1.2 Mach at 1000 yards. Even if the production rifles only get 1 MOA, that's an awesome potential for long range.

Anyone have time behind the new Ruger long range rifle? I know it’s brand new and there probably aren’t many of any in the shops yet, but I have some reservations about the 2 piece lower receiver. I’m not saying it’s a bad thing, but how will this 2 piece lower receiver hold up under field conditions and if it doesn’t, how would a failing lower impact accuracy or reliability? They have a new multi mag retention system design that accepts several different manufactures mags. We all know the weakest part of any detachable mag system is the mag itself. The articles I’ve found on Ruger’s RPR don’t go into how much testing went into the production rifle; they just discuss other AR type attributes the rifle exudes. They fall short in reviewing the rifle and its 2 piece lower with innovating mag retention system over time. The only thing I saw about the 2 piece lower was the construction process in American Rifleman that says “…the right and left halves simplify manufacturing and allows more precise control of machining in the mag well and makes assembly of small components easier as they can be positioned in one half before the other half is attached.” This attaching is where I have questions. How is it locked in place? What happens after several hundred recoil cycles from high velocity rounds going down the pipe try to loosen things up or how does it hold up when the gun gets banged around in normal field conditions? It's price point and AR type attributes are very attractive, but I'm not ready to abandon my R700 just to try a new entrant in the long range rifle game.

Update - After testing several brands of ammo with different bullet weights, I contacted JP. They said I may be the first to have accuracy issues with the GMR-13. They said to send it back. I shipped it back. After testing, JP engineer agreed with my findings. They are replacing the barrel. Should be getting it back next week. I received am email today from JP. They said my GMR-13 upper has a new super match barrel! JP tested it at 100 yards with Freedom Munitions 124g XTP. 5 shot group at 100 yards was 1.78 inches. They shipped it back today. Hopefully it will be here the first of next week. Here's the test target John Paul himself shot with my new barrel.

If your brass is dented with a low mass BC, your gun is over gassed and the extractor is loosing control of your brass with the higher cyclic rate. The dent occurs as the bolt returns & kicks the brass forward striking the ejection port and then flips it out of the gun. JP has a great Gas Gun video that explains this really well. The fix is to close the gas down till it doesn't lock the bolt back on last round and then start opening it up 1/4 turn at a time till it locks back. Give it another 1/4 turn open and it should be fine with most factory loads & stop denting the brass. If it still dents the brass, you can fine tune it more with a lighter buffer and go through the gas adjustment again. Less gas with a LMBCG and lighter buffer, adjusted for the correct cyclic rate, should stop denting the brass and give you a smooth running gun with virtually no recoil impulse.

Pardon my ignorance, but what's a JP SCS?

Update - After testing several brands of ammo with different bullet weights, I contacted JP. They said I may be the first to have accuracy issues with the GMR-13. They said to send it back. I shipped it back. After testing, JP engineer agreed with my findings. They are replacing the barrel. Should be getting it back next week.

Yes, Polo matches rock. I did say I wasn't a Jesse Tischauser. I'll take 6 seconds shoulder 2 should any day at my age. ;-)

I have an M1 super 90, it has the pistol grip and I load with my support hand. I may not be as fast as the super squad or Jesse Tischauser, but I can quad load 8 off the shoulder and back on target in 6 seconds. Hasn't hurt me in a 3 Gun Nation Club match so far. I also have another one for a backup that's set up the same way but without the pistol grip. It loads about the same.

Someone once told me they run like ball bearings on butter. I had a hard time grasping that concept until I racked the slide on my brand new Infinity. There it was, as smooth as ball bearings on butter. And then I pulled the trigger. There's really no comparison to any other 1911/2011 fire control system. It's just that much better. It is amazing what Brandon does with his SVIs.

I had a similar issue with my 1991 H&K M1 super 90. I looked at the back side of the hammer and noticed is was showing some wear. I looked at the end of the carrier and it looked the same way where it resets the hammer. I took some 400 wet/dry and polished both the back of the hammer and the end of the carrier. Then I buffed everything to a mirror finish with semichrome. I also polished the lifter actuator and the area on the backside of the carrier where it actuates the lifter for the next shell. After polishing/buffing, it now runs fine with a 10 round Xrail.

That makes more sense, thanks!

I've searched the forum for anything about how target rule 8.6 is applied for both regional & club in a course of fire. I can't find anything. It appears the PCR can be used on ANY target stipulated in the WSB for paper, steel or clay. The rule is kinda confusing the way it's written. Are shooters using a PCR for all targets on a match stage for all 3 guns?

I've seen several posts like yours and nobody every posts how they fixed the issue. They talk about replacing all the springs and nothing helps. I guess they either finally took it to a gunsmith or sold the gun. Here's my experience with my 25 year old Super 90 when it started having failures to load the next round on the 4th or 5th shot. I tried replacing the recoil spring and that made it worse. I started thinking, why would it get worse? It acts like it's short stroking and slowing the bolt down. Then I thought, what does the backside of the hammer and bolt carrier look like? Mine was really rough and looked like it started to pull metal where the carrier contacts the hammer to reset the sear and the lifter lever as it cycles. I took some 400 grit and blended the surfaces smooth, and then used the Dremel polishing wheel to give it a mirror surface. The Benelli now cycles anything I put through it; even the super cheap WM Winchester Universals. Your experience may be different. Good luck!

Just my opinion and my experience with the .40SW in my Glock 35, STI Edge & SVI Infinity. I've used the Xtreme 180s at 1.200 OAL in the 2011s. I had issues with set back when I just took the case mouth back to spec after pressing the plated bullets into the case. Crimping the plated bullets is kinda tricky if you want to make major PF. You are correct that jacketed bullets need a cannelure if you want to crimp. I don't try to make major PF any more with plated bullets. When I did load major with Rainier plated 180s, it caused the copper plating to strip off when I put enough crimp to prevent set back. The accuracy went away also. Now I just shoot minor with plated bullets and crimp the heck out of them. Recoil is like a .22, no set back, accuracy is awesome and no shedding of copper plating. Your experience my vary.

What did you find that fixed your issue?

I'm thinking about plugging my 10 round tube to use in Heavy metal. The rule doesn't say you can't. What are other people doing? Here's the rule - 7.5.3.10 Shotguns in Heavy Optics Division SHALL NOT hold more than eight (8) shells in the magazine total or start a stage with more than nine (9) shells total in the shotgun. (Rule 3.7)

I make my own grease. I blend synthetic oil with high pressure chassis red grease that's really tacky. I mix it half & half most of the time, depending on the temperature I'll be shooting the pistol, I'll mix it a little thinner for cold weather. Clean up is a breeze. Residue just wipes off. Gun runs like ball bearings on butter.

STI sets their guns up to run on factory ammo or properly sized reloads. They don't run well on once fired .40 brass with the infamous Glock bulge at the base of the case. If your re-manufactured ammo wasn't sized all the way to the rim, it will cause the gun to choke. Get yourself a Dillon case gauge and check every reloaded round before it goes into your gun. Another issue can be the bullet crimp. If the crimp isn't tight enough, the bullet will get pushed back into the case as it gets stripped out the mag and slows down the slide in recoil like a shock absorber slows the rebound of a tire on your car after it hits a bump. If the slides' forward motion is impeded by pressing the bullet into the case, the recoil spring doesn't have enough energy to push the slide all the way back into battery. Measure the overall length (OAL) of the re-manufactured round, and then try pushing the bullet into the case by holding the round against a solid object like a table with the bullet end against the table. Lean on it with all your weight and then measure it again. If its OAL didn't change, the crimp should be fine. If you don't have a case gauge or a caliper to measure the OAL, you could always try running some factory ammo through the gun and see if it still chokes.

What the heck do the 3GN rules mean by a Featured Club Concession rifle? Is it a just a pistol caliber rifle?

Is there gonna be any flags or streamers down range to help with wind guestimation from the van?