bmiller Posted December 23, 2016 Share Posted December 23, 2016 21 minutes ago, Bob Hostetter said: In the beginning only as a complete gun or upper. As inventory levels allow, we will offer the individual parts. Good to know. Do the guns run cleaner than a blowback? Link to comment
Bob Hostetter Posted December 23, 2016 Share Posted December 23, 2016 It does run a little cleaner then the blowback model. All testing of the blowback and the DI has been done with factory 115's and 124's, no ultra light handloads have been used. Link to comment
1911luvr Posted December 23, 2016 Share Posted December 23, 2016 It does run a little cleaner then the blowback model. All testing of the blowback and the DI has been done with factory 115's and 124's, no ultra light handloads have been used.I run 100gr to 160gr in my blowback and everything runs, however I'd like a tuned DI to help stop muzzle rise in competition. DI should make plate racks even faster, and super fast transition in steel challenge. Even if the DI doesn't run every weight projectile, I'd still take it if I can tune it to a couple of my common loads to shoot plate racks and spinners. Sent from my iPhone using Tapatalk Link to comment
jkrispies Posted December 23, 2016 Share Posted December 23, 2016 44 minutes ago, 1911luvr said: I run 100gr to 160gr in my blowback and everything runs, however I'd like a tuned DI to help stop muzzle rise in competition. DI should make plate racks even faster, and super fast transition in steel challenge. Even if the DI doesn't run every weight projectile, I'd still take it if I can tune it to a couple of my common loads to shoot plate racks and spinners. Sent from my iPhone using Tapatalk :-) Link to comment
1911luvr Posted December 25, 2016 Share Posted December 25, 2016 For those that have shot the JP GMR-13 as well as an NFA (be it PSA, Spartan, ATI)--the JP website says "The end result is a system that cycles with virtually no recoil." Is there a difference (reduction?) in the felt recoil impulse between the JP and the NFA variants?I have the ATI 16" rifle variant of the NFA, and two friends have the JP GMR-13. First, yes there is a huge difference between them in stock configuration. The JP recoils straight back with no muzzle rise, so if you double tap 8" steel at 25 yards, the second round will always hit unless you flinch badly. The ATI has a bolt slamming action combined with muzzle rise that moves the barrel up and to the right for right handed shooters making quick followup shots more difficult. The difference in felt recoil between the rifles comes from the difference in buffer configuration and muzzle brake. The ATI has a buffer that is barely enough to slow the bolt blowback, so you get a slamming jolt with each shot. The JP comes with their silent captured spring system which makes a very noticeable difference. Rather than go to a heavy 9oz buffer and .308 spring in my ATI, I added the JP SCS and removed the weight from my bolt carrier to work with the SCS system. This definitely helped, but in side-by-side comparison today it still has more muzzle rise than the JP. The ATI has a birdcage style comp which basically has no lower openings so it's actually a bit of a brake, but poor in comparison to the JP tactical brake on the GMR-13. I will be adding that next so I hopefully it will take care of the last bit of muzzle rise. Sent from my iPhone using Tapatalk Link to comment
Aircooled6racer Posted December 25, 2016 Share Posted December 25, 2016 Hello: I removed the weight from my BCG as well and shot it. It was too light so I added an aluminum slug in the carrier to bring the weight up to just over 13 ozs. That little amount made a big difference. Very flat shooting even with a birdcage comp. Another thing on the JP is the weight of their hand guards which are on the heavy side. That will keep the front end down as well. A barrel weight on the end will do the same. I have a friend getting a JP next month so we can test it against my build to see what works. There is no daught that JP make good stuff and test things to make a good product. Just wondering if it can be made even better? Thanks, Eric Link to comment
funkymonkey1111 Posted December 25, 2016 Share Posted December 25, 2016 51 minutes ago, 1911luvr said: I have the ATI 16" rifle variant of the NFA, and two friends have the JP GMR-13. First, yes there is a huge difference between them in stock configuration. The JP recoils straight back with no muzzle rise, so if you double tap 8" steel at 25 yards, the second round will always hit unless you flinch badly. The ATI has a bolt slamming action combined with muzzle rise that moves the barrel up and to the right for right handed shooters making quick followup shots more difficult. The difference in felt recoil between the rifles comes from the difference in buffer configuration and muzzle brake. The ATI has a buffer that is barely enough to slow the bolt blowback, so you get a slamming jolt with each shot. The JP comes with their silent captured spring system which makes a very noticeable difference. Rather than go to a heavy 9oz buffer and .308 spring in my ATI, I added the JP SCS and removed the weight from my bolt carrier to work with the SCS system. This definitely helped, but in side-by-side comparison today it still has more muzzle rise than the JP. The ATI has a birdcage style comp which basically has no lower openings so it's actually a bit of a brake, but poor in comparison to the JP tactical brake on the GMR-13. I will be adding that next so I hopefully it will take care of the last bit of muzzle rise. Sent from my iPhone using Tapatalk Thanks for that info! Please be sure to check in once you've got the JP brake installed Link to comment
1911luvr Posted February 8, 2017 Share Posted February 8, 2017 Thanks for that info! Please be sure to check in once you've got the JP brake installedSorry it took so long to get back to this. I have run the JP brake in a couple matches now and it is much improved. My dot bounce is noticeably reduced, so I have no trouble keeping the dot on the plate during quick double taps. Definitely worth the upgrade. Sent from my iPhone using Tapatalk Link to comment
Flatland Shooter Posted February 9, 2017 Share Posted February 9, 2017 On 12/19/2016 at 8:40 PM, funkymonkey1111 said: For those that have shot the JP GMR-13 as well as an NFA (be it PSA, Spartan, ATI)--the JP website says "The end result is a system that cycles with virtually no recoil." Is there a difference (reduction?) in the felt recoil impulse between the JP and the NFA variants? A gentleman in our squad noticed I have a Hiperfire trigger in my PCC and requested permission to give it a try. He said he was surprised how much more felt recoil was present in my PSA 9mm carbine compared to his JP carbine. He was shooting my 132 PF reloads in my gun and he was shooting factory 9mm in his JP 9mm. I did not shoot his. If he is correct, then there is reduced felt recoil with the JP system. Link to comment
1911luvr Posted February 9, 2017 Share Posted February 9, 2017 A gentleman in our squad noticed I have a Hiperfire trigger in my PCC and requested permission to give it a try. He said he was surprised how much more felt recoil was present in my PSA 9mm carbine compared to his JP carbine. He was shooting my 132 PF reloads in my gun and he was shooting factory 9mm in his JP 9mm. I did not shoot his. If he is correct, then there is reduced felt recoil with the JP system.What muzzle device and buffer system are you running?Sent from my iPhone using Tapatalk Link to comment
Flatland Shooter Posted February 9, 2017 Share Posted February 9, 2017 2 hours ago, 1911luvr said: What muzzle device and buffer system are you running? Sent from my iPhone using Tapatalk Birdcage on the muzzle (at least until someone can show me that one of the high dollar ones help) and the stock 9mm recoil spring. The carbine buffer weighs 5.5 ounces. Link to comment
1911luvr Posted February 9, 2017 Share Posted February 9, 2017 Birdcage on the muzzle (at least until someone can show me that one of the high dollar ones help) and the stock 9mm recoil spring. The carbine buffer weighs 5.5 ounces.I believe he just showed you. LolSent from my iPhone using Tapatalk Link to comment
Flatland Shooter Posted February 9, 2017 Share Posted February 9, 2017 25 minutes ago, 1911luvr said: I believe he just showed you. Lol Sent from my iPhone using Tapatalk Not really. He commented on my gun having more felt recoil but his seemed to have a bit more muzzle movement. His gun was a bit heavier. But then, he was shooter hotter ammo. Need to compare apples to apples. Link to comment
Aircooled6racer Posted February 9, 2017 Share Posted February 9, 2017 9 hours ago, Flatland Shooter said: Birdcage on the muzzle (at least until someone can show me that one of the high dollar ones help) and the stock 9mm recoil spring. The carbine buffer weighs 5.5 ounces. Hello: Try a regular 223 carbine spring and see how that works for you. It should take out some of the recoil you are getting. Thanks, Eric Link to comment
Benl Posted February 9, 2017 Share Posted February 9, 2017 (edited) I built a lefty using Stag upper/lower/BCG (during the 20 minutes they made a 9mm rifle.) Shooting a 9mm blowback kindda sucks when you're left-handed; I was really happy that Stag sold a lefty. I'm sorry I didn't know they would discontinue so fast, or I would have bought some spare parts while I could (spare BCG.) Luckily, most of the parts are stock Colt, so it's no big deal. The Stag magazines are very hit or miss, but Metalform mags are 100% reliable. I've since replaced the iron sights with an Eotech. Edited February 9, 2017 by Benl Link to comment
Benl Posted February 9, 2017 Share Posted February 9, 2017 14 hours ago, Flatland Shooter said: A gentleman in our squad noticed I have a Hiperfire trigger in my PCC and requested permission to give it a try. He said he was surprised how much more felt recoil was present in my PSA 9mm carbine compared to his JP carbine. He was shooting my 132 PF reloads in my gun and he was shooting factory 9mm in his JP 9mm. I did not shoot his. If he is correct, then there is reduced felt recoil with the JP system. You might also try a LanTac Dragon brake with a Blitzkrieg Components hydraulic buffer; that combo really knocked my recoil down significantly. Link to comment
1911luvr Posted February 9, 2017 Share Posted February 9, 2017 Not really. He commented on my gun having more felt recoil but his seemed to have a bit more muzzle movement. His gun was a bit heavier. But then, he was shooter hotter ammo. Need to compare apples to apples.I have compared them apples to apples and there is a very noticeable difference. Two of my friends have the JP GMR13 rifle and we all sighted them in together. I got my rifle first, so I had already run it and found the stock buffer caused lots of bolt slamming, leading to that feeling of heavier recoil and excessive dot bounce. I put the JP silent captured spring in it and it helped relieve some of the bolt slam, and a little dot bounce. With the same ammo as my friends, I had more dot bounce with every load than they did, so I bought the same JP brake theirs came with. Problem solved. I can double or triple tap plates without the dot bouncing off the plate. I'm going to try a lighter JPSCS spring and swap a tungsten weight for steel to see if I can get the overall movement down to match our 5.55 3-gun rifles which barely have any recoil feel. Sent from my iPhone using Tapatalk Link to comment
Derwoodski Posted March 27, 2017 Share Posted March 27, 2017 On 6/15/2016 at 11:48 PM, Alaskapopo said: I used to have a Colt and an RRA that used UZI and Colt mags. I believe 32 is the most and no extensions. Pat Taylor freelance makes a +10 for colt mags. I have one on a metalform 32 rounder er now 42 rounder. I think it will also fit ASC mags as well but haven't tested it. Link to comment
latenightlegend Posted March 28, 2017 Share Posted March 28, 2017 I have compared them apples to apples and there is a very noticeable difference. Two of my friends have the JP GMR13 rifle and we all sighted them in together. I got my rifle first, so I had already run it and found the stock buffer caused lots of bolt slamming, leading to that feeling of heavier recoil and excessive dot bounce. I put the JP silent captured spring in it and it helped relieve some of the bolt slam, and a little dot bounce. With the same ammo as my friends, I had more dot bounce with every load than they did, so I bought the same JP brake theirs came with. Problem solved. I can double or triple tap plates without the dot bouncing off the plate. I'm going to try a lighter JPSCS spring and swap a tungsten weight for steel to see if I can get the overall movement down to match our 5.55 3-gun rifles which barely have any recoil feel. Sent from my iPhone using TapatalkWould you want a heavier spring to reduce felt recoil? Definitely keep us posted about tuning the SCS. I have the same issues and ordered everyone of the JP springs. Sent from my iPhone using Tapatalk Link to comment
1911luvr Posted March 28, 2017 Share Posted March 28, 2017 Would you want a heavier spring to reduce felt recoil? Definitely keep us posted about tuning the SCS. I have the same issues and ordered everyone of the JP springs. Sent from my iPhone using TapatalkA lighter spring and buffer with lower power factor loads will be smoother. It's a combination of reducing bolt slam from the force of the spring and heavy weight, while also keeping the bolt closed long enough. Shooting hot loads with a light buffer system could be dangerous if the bolt blows back too soon. I'm still playing with different loads for different games (USPSA/Steel Challenge), so I haven't changed from the stock JPSCS weights a springs yet. Sent from my iPhone using Tapatalk Link to comment
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