TNREDNECK Posted December 24, 2018 Share Posted December 24, 2018 How many ways are there to install a 9mm PCC Barrel in a upper receiver ? Link to comment
TNREDNECK Posted December 24, 2018 Share Posted December 24, 2018 (edited) Do most competion shooters pay a gunsmith to install there barrels , due to the highly technical procedures that are required ? Edited December 24, 2018 by TNREDNECK Wrong word used Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 31 minutes ago, TNREDNECK said: How many ways are there to install a 9mm PCC Barrel in a upper receiver ? Only goes in one way that I am aware of. Barrel goes in with alignment pin up. Torque the barrel nut down. Install handguard. Shoot Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 33 minutes ago, TNREDNECK said: Do most competion shooters pay a gunsmith to install there barrels , due to the highly technical procedures that are required ? I would say probably 80% or higher do this themselves. I'm pretty sure one could train about anyone to do this properly. Link to comment
TNREDNECK Posted December 24, 2018 Share Posted December 24, 2018 That’s My understanding also , so there is no way to tune it or adjust it ,you install the barrel the hand guard attach the optic of your choice,move then to a bench and sight it in ? Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 1 minute ago, TNREDNECK said: That’s My understanding also , so there is no way to tune it or adjust it ,you install the barrel the hand guard attach the optic of your choice,move then to a bench and sight it in ? For the most part. That's the Beauty of an AR15. Pretty much plug and play. Link to comment
TNREDNECK Posted December 24, 2018 Share Posted December 24, 2018 So what would you check if you installed a new barrel and could not get consistent groups at your starting distance from a bench at 25 yards ? Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 15 minutes ago, TNREDNECK said: So what would you check if you installed a new barrel and could not get consistent groups at your starting distance from a bench at 25 yards ? For me it starts when u install it initially. Checking the fit to the receiver ( Making sure it fits straight and no excessive play in the receiver). After that torque the barrel nut to spec. Install handguard. Then if I had problems on the bench I would check optic first. Making sure it didn't become loose or is broken. Next I would clean it . Then I would try different ammo ( some barrels don't like certain types of ammo ) . Also shoot a 100 or so rounds through it to break it in. If everything above was done and I didn't see any improvement in accuracy then I could only assume it must be a issue with the barrel itself. Link to comment
dmshozer1 Posted December 24, 2018 Share Posted December 24, 2018 27 minutes ago, TNREDNECK said: So what would you check if you installed a new barrel and could not get consistent groups at your starting distance from a bench at 25 yards ? One thing that hardly ever gets mentioned is the barrel crown. Down the road from me is world renowned barrel maker Hart Barrels. They have reluctantly recrowned barrels from other manufactures for me. What a difference! I am talking all calibers, all rifles, all pistols. It has to be near perfect. Take the very best barrel with a bad crown, it will never shoot up to it's potential. The barrel nut has to be a good one to correctly hold the barrel. Most are cheep. Of course you have to realize that barrels can be picky about what they like as far as reloads and factory ammo. Good luck. Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 2 minutes ago, dmshozer1 said: One thing that hardly ever gets mentioned is the barrel crown. Down the road from me is world renowned barrel maker Hart Barrels. They have reluctantly recrowned barrels from other manufactures for me. What a difference! I am talking all calibers, all rifles, all pistols. It has to be near perfect. Take the very best barrel with a bad crown, it will never shoot up to it's potential. The barrel nut has to be a good one to correctly hold the barrel. Most are cheep. Of course you have to realize that barrels can be picky about what they like as far as reloads and factory ammo. Good luck. +1 Link to comment
TNREDNECK Posted December 24, 2018 Share Posted December 24, 2018 13 minutes ago, dmshozer1 said: One thing that hardly ever gets mentioned is the barrel crown. Down the road from me is world renowned barrel maker Hart Barrels. They have reluctantly recrowned barrels from other manufactures for me. What a difference! I am talking all calibers, all rifles, all pistols. It has to be near perfect. Take the very best barrel with a bad crown, it will never shoot up to it's potential. The barrel nut has to be a good one to correctly hold the barrel. Most are cheep. Of course you have to realize that barrels can be picky about what they like as far as reloads and factory ammo. Good luck. My gun JP GMR 15 so Barrel nut is not it , shot multiple weights of ammo , factory and hand loads will not group and has 2 or 3 fliers in every 5 shot group . Removed the lightweight barrel and reinstalled the JP barrel. Shoots great again , what do you think? Link to comment
dmshozer1 Posted December 24, 2018 Share Posted December 24, 2018 31 minutes ago, TNREDNECK said: My gun JP GMR 15 so Barrel nut is not it , shot multiple weights of ammo , factory and hand loads will not group and has 2 or 3 fliers in every 5 shot group . Removed the lightweight barrel and reinstalled the JP barrel. Shoots great again , what do you think? With a decent rest for shooting, a bad crown is the exact indication for flyers. Do you have a magnifer to look at the crown? It does't take much. Is the barrel straight cut or does it have a beveled crown? Straight is easy to get a good one. When it's beveled it has to be right on the money. The gas that comes out before the bullet has more of an effect on the bullet than a straight cut. Even though a 16" 9mm barrel does not have a lot of gas exiting it, it still might have an effect on a bad crown. That is how they explained it to me. Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 3 minutes ago, dmshozer1 said: With a decent rest for shooting, a bad crown is the exact indication for flyers. Do you have a magnifer to look at the crown? It does't take much. Is the barrel straight cut or does it have a beveled crown? Straight is easy to get a good one. When it's beveled it has to be right on the money. The gas that comes out before the bullet has more of an effect on the bullet than a straight cut. Even though a 16" 9mm barrel does not have a lot of gas exiting it, it still might have an effect on a bad crown. That is how they explained it to me. 11° crown is what is stated on their website Link to comment
dmshozer1 Posted December 24, 2018 Share Posted December 24, 2018 4 minutes ago, Mac-pcc said: 11° crown is what is stated on their website Yup, Target crown. Just a thought. Have you shot it with out the comp? I know at least on some of my rifles, a comp change has given me different groups and a change of impact. Link to comment
Stymie12000 Posted December 24, 2018 Share Posted December 24, 2018 If not already stated! Also could be baffle strikes on the comp. I ran into this with an open gun! Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 21 minutes ago, dmshozer1 said: Yup, Target crown. Just a thought. Have you shot it with out the comp? I know at least on some of my rifles, a comp change has given me different groups and a change of impact. It a pinned and welded comp. Link to comment
MoRivera Posted December 24, 2018 Share Posted December 24, 2018 (edited) Can one see baffle strikes in a comp/brake...like little nicks or the like? Could carbon buildup also cause it? Edited December 24, 2018 by MoRivera Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 3 minutes ago, MoRivera said: Can one see baffle strikes in a comp/brake...like little nicks or the like? Not on my father's barrel. I thought it might be hitting the comp but I saw no evidence of a hit. Link to comment
MoRivera Posted December 24, 2018 Share Posted December 24, 2018 (edited) I do notice when cleaning out the comp that the edges are quite sharp, so maybe there are some very small burs that are affecting things? Or perhaps something in the comp chamber shape is causing a slight skew of the bullet as it clears the main barrel and is somehow adversely affected by the next two baffle surfaces? But then again, if you look at MBX's own tests, it seems fine. Edited December 24, 2018 by MoRivera Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 2 minutes ago, MoRivera said: I do notice when cleaning out the comp that the edges are quite sharp, so maybe there are some very small burs that are affecting things? It almost has to be a crown issue. The comp is overbored by a good bit. Link to comment
MoRivera Posted December 24, 2018 Share Posted December 24, 2018 1 minute ago, Mac-pcc said: It almost has to be a crown issue. The comp is overbored by a good bit. That I noticed as well, so you would think the bullet is clearing them fine. Could the crown have gotten nicked while cleaning? Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 4 minutes ago, MoRivera said: That I noticed as well, so you would think the bullet is clearing them fine. Could the crown have gotten nicked while cleaning? I can't speak for the others but we used a bore snake on my father's. I don't know how u could nick it with a bore snake. Link to comment
MoRivera Posted December 24, 2018 Share Posted December 24, 2018 Maybe a shard of copper jacket or something, I dunno. The tests that MBX did in the pics earlier say they were off a simple rest. Link to comment
Mac-pcc Posted December 24, 2018 Author Share Posted December 24, 2018 6 minutes ago, MoRivera said: Maybe a shard of copper jacket or something, I dunno. The tests that MBX did in the pics earlier say they were off a simple rest. Yeah I don't know either. We used Caldwell dead shot sand bags for our test Link to comment
ericskennard Posted December 24, 2018 Share Posted December 24, 2018 I have threaded and chambered a bunch of long range rifle barrels. I use Brux, Bartlein, and Krieger. I will tell you barrels are like finger prints, no two are the same. Also regarding the lead sled, the sled can induce flyers. You may see better results just using a sand bag or bipod. Link to comment
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