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View Full Version : Trying to find the issue with my T97 Rifle, need some help



PsycO
08-09-2017, 04:33 PM
Hi,

I've recently aquired a norinco T97NSR 5.56. It,s a pretty nice rifle and i love shooting it, but i have an issue and i need some advice on possible cause. I explain the problem :
So i've zeroed it a 100m. I tried a lot of ammo and the one it like the most is Federal American Eagle 62gr .223. Now i setup and shoot 2 LAR-15 magazine(10 rounds each) at a medium pace ( 1 shot / 20-30 sec ) and they all land near the bulleye at around 1.5MOA. That's decent in my opinion for a 'battle rifle'. Now i full 2 more magazine and go change the target, the barrel is cooling in the meantime. Then i go prone again with my bipod, start shooting and the POI start shifting up and go wild. After 4 magazine the rifle POI is now 1 MIL up and gone wild to like 4-5 MOA. After i see no point shooting for precision and i do some rapid fire shooting drill.
After the range i run a boresnake with a little oil through it.
Next shooting is always the same, accurate till the 3rd mags and start going wild till the 4th and stay there after.

Don't know what is the issue and how i can correct it. I hope it's not the ammo since there is not a lot of round it shoot great, only 1 in fact. I wanna stay with factory ammo since there is no point in reloading for that rifle as it destroy the brass when it eject.

I've not did any 'break-in' of the barrel as i supposed it's chrome lined anyway, as a semi-auto rifle.

All the other ammo i tried in it do horrible group, 3 more MOA exept the Federal American Eagle 5.56 green tip which is aroung 2 moa.

So thx for helping me with the issue

kennymo
08-09-2017, 04:46 PM
It probably likes ammo around 60 grains or more due to the twist rate?

The group opening up sounds very much like a heat issue. Might hold accuracy longer with a slower rate of fire?

GhostOf'33
08-09-2017, 08:29 PM
Interesting. I take it you sighted in with the bipod.

I assume nothing is touching the barrel support wise, if you had something underneath the barrel that usually causes the shots to string vertically. (I don't think this is the problem in your case)

My best guess is that it is heat related, either the rifle wants to shoot high when hot, or the mirage off the hot barrel is affecting your sight picture. I think the best cure would be to slow down your rate of fire, or allow the barrel to cool (lukewarm to touch is what I use), or both.

My 2 cents.

RobertMcC
08-09-2017, 09:07 PM
Sounds like something is touching.

Danimal85
08-09-2017, 10:27 PM
The biggest issue i had with my T97 was that it liked to smash rounds into the feed ramp so that it pushed the bullets into the feed ramp and they would get smashed back into the case and spill powder all over the action while jamming the gun. I built up the magwell so that it held the mags at a better angle so the rounds hit the feed ramp at a better angle while still using unmodified STANAG mags.

Justice
08-10-2017, 10:13 AM
"...with my bipod..." That's your problem. Not the ammo. Assuming the bipod on the barrel is pushing the barrel up. The fix is to quit using the bipod.
"...destroy the brass when it ejects..." That's highly unlikely. Brass can get bent a bit and be fixed with no fuss.

PsycO
08-10-2017, 02:57 PM
Alright some precision here:

First kennymo : Yes the barrel twist is 1/7, quite fast, and from i've read (no expert but read a lot) the best is 62 to 77 grain bullet. Each bullet i tried were at least 62 grain bullet, and even on the slower end of the bullet spectrum they dont perform very well exept one brand. I even had issue with nosler varmageddon that seem to destroy itself from the centrifugal force never reaching the target at 100m. For the heat problem, i tried it one time. The barrel was as cold to touch as possible at 29Degree celcius under the sun of my shooting pit. I also left the gun under the sun before shooting my first mags to be sure the gun was already at the pit temp to be sure it was not a heat related problem. Same result. I need to mention that i left the barrel cool for like 10-15 min before the first 2 mags and the other. And the gun is pretty well ventilated, so i dont think about a heat issue.

Next Ghost and robert and Justice: No nothing is touching the barrel, i'll post the picture of my setup so you can judge yourself. The bipod is attached to a custum sling stud i've installed on my lower hand guard.

Next Danimal: I think i have the next generation(gen2) of T97NSR, they have been modified in the magazine well so the mag fit perfectly, the LAR-15 mags are gen2 too and in around 250 round fired from it from these mags since i buyed the rifle a couple months ago i never had a single fail.

Next Justice: I used the bipod for all the shot from start to finish. And it is installed on the lower not on the barrel. For the brass i'm no really into it, if they can be fixed after being bent its nice i keep them all anyway. And i need to use my bipod or tripod. This rifle will be used for coyote hunting this winter, and i wont be able to do 200m shots if i'm not using some kind of support. Thats why i zeroed the rifle using it too.

I also contacted a gunsmith that know the rifle and i pointed me out some possible cause, the number one is the crowns. Maybe the crown is not perfectly concentric with the barrel and some disposit messes with it. That make sense since when i do a quick clean i remove the stuff and it shoot fine after. I'll take a look at it and maybe have it re-crowned. Also possibly the barrel retention screws. I'll look at those two possible cause this weekend.

If you have some idea let me know and i'll add them to the check list.

Thx for you time.

3194

PsycO
08-10-2017, 03:03 PM
Alright some precision here:

First kennymo : Yes the barrel twist is 1/7, quite fast, and from i've read (no expert but read a lot) the best is 62 to 77 grain bullet. Each bullet i tried were at least 62 grain bullet, and even on the slower end of the bullet spectrum they dont perform very well exept one brand. I even had issue with nosler varmageddon that seem to destroy itself from the centrifugal force never reaching the target at 100m. For the heat problem, i tried it one time. The barrel was as cold to touch as possible at 29Degree celcius under the sun of my shooting pit. I also left the gun under the sun before shooting my first mags to be sure the gun was already at the pit temp to be sure it was not a heat related problem. Same result. I need to mention that i left the barrel cool for like 10-15 min before the first 2 mags and the other. And the gun is pretty well ventilated, so i dont think about a heat issue.

Next Ghost and robert and Justice: No nothing is touching the barrel, i'll post the picture of my setup so you can judge yourself. The bipod is attached to a custum sling stud i've installed on my lower receiver.

Next Danimal: I think i have the next generation(gen2) of T97NSR, they have been modified in the magazine well so the mag fit perfectly, the LAR-15 mags are gen2 too and in around 250 round fired from it from these mags since i buyed the rifle a couple months ago i never had a single fail.

Nest Justice: I sed the bipod for all the shot from start to finish. And it is istalled on the lower not on the barrel. For the brass i'm no really into it, if they can be fixed after being bent its nice i keep them all anyway. And i need to use my bipod or tripod. This rifle will be used for coyote hunting this winter, and i wont be able to do 200m shots if i'm using using some kind of support. Thats why i zeroed the rifle using it too.

I also contacted a gunsmith that know the rifle and he pointed me out some possible cause, the number one is the crowns. Maybe the crown is not perfectly concentric with the barrel and some disposit messes with it. That make sense since when i do a quick clean i remove the stuff and it shoot fine after. I'll take a look at it and maybe have it re-crowned. Also possibly the barrel retention screws. I'll look at those two possible cause this weekend.

If you have some idea let me know and i'll add them to the check list.

Thx for you time.

3194

shadowwarrior
08-17-2017, 09:56 PM
The biggest issue i had with my T97 was that it liked to smash rounds into the feed ramp so that it pushed the bullets into the feed ramp and they would get smashed back into the case and spill powder all over the action while jamming the gun. I built up the magwell so that it held the mags at a better angle so the rounds hit the feed ramp at a better angle while still using unmodified STANAG mags.

Can you elaborate on the magweel build up? My T97 does the same thing occasionally but it looks like they get pushed up and left of the chamber but that could be where they end up after the feed ramp hits.