72stick Posted July 24, 2015 Share Posted July 24, 2015 He emailed me this.... I'm still searching for the best ammo to run in the GMR. Best 147g plated performance with 3.5g titegroup @ 100 yards isn't very impressive, 6-8 MOA. I tried factory115 FMJ @ 50 yards & it's a little better. I haven't tested 124 or 147 factory FMJs yet. I had a little issue with ejector coming loose. JP sent a new style ejector with counter sunk holes & iron screws instead of the stainless set screws. They said the stainless won't stay tight. Sent from BJ's iPhone 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. Link to comment Share on other sites More sharing options...
72stick Posted August 5, 2015 Share Posted August 5, 2015 (edited) He emailed me this.... I'm still searching for the best ammo to run in the GMR. Best 147g plated performance with 3.5g titegroup @ 100 yards isn't very impressive, 6-8 MOA. I tried factory115 FMJ @ 50 yards & it's a little better. I haven't tested 124 or 147 factory FMJs yet. I had a little issue with ejector coming loose. JP sent a new style ejector with counter sunk holes & iron screws instead of the stainless set screws. They said the stainless won't stay tight. Sent from BJ's iPhone 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. Edited August 5, 2015 by 72stick Link to comment Share on other sites More sharing options...
twowheels Posted August 24, 2015 Share Posted August 24, 2015 (edited) Nice! I have a flat top colt that uses...colt mags. Its a lot of fun to shoot. The jp wasn't out when I bought it or I might have just bought the jp. I did have a few occasional issues with it in a competition. The extractor hook didn't capture the cartridge rim on a couple occasions. I dismantled the gun and polished and tensioned the extractor (it seemed too tight) and haven't shot it since. I need to take it out again and run some ammo through it. Edited August 24, 2015 by twowheels Link to comment Share on other sites More sharing options...
Jesse Tischauser Posted September 11, 2015 Share Posted September 11, 2015 Really fighting the urge to buy one of these. Link to comment Share on other sites More sharing options...
Stlhead Posted September 12, 2015 Share Posted September 12, 2015 Don't fight it, I ordered another and paid the short tax. Nothing like a 2 stamp gun! Link to comment Share on other sites More sharing options...
wgj3 Posted September 12, 2015 Share Posted September 12, 2015 (edited) I'm just waiting for mine now too. Couldn't hold back. Red dot for sight? Edited September 12, 2015 by wgj3 Link to comment Share on other sites More sharing options...
wgj3 Posted September 13, 2015 Share Posted September 13, 2015 What about running something like "Major" 9 through these rifles? Link to comment Share on other sites More sharing options...
72stick Posted September 14, 2015 Share Posted September 14, 2015 (edited) 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. Edited September 14, 2015 by 72stick Link to comment Share on other sites More sharing options...
72stick Posted September 14, 2015 Share Posted September 14, 2015 (edited) I'm just waiting for mine now too. Couldn't hold back. Red dot for sight? 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. Edited September 14, 2015 by 72stick Link to comment Share on other sites More sharing options...
wgj3 Posted September 14, 2015 Share Posted September 14, 2015 Thanks for the thoughts! Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now