I brought a newly cleaned T97NSR Gen 2 to the range to shoot my recently bought Barnaul 223Rem 55Gr FMJBT ammo. More than a third of the bullets gave me a keyhole on the target paper. I tested my rifle with 55Gr American Eagle FMJ, 55Gr Independence FMJ as well as 55Gr Barnaul JHP ammo. All came out fine. I thought the Barnaul 55Gr FMJBT was defective. However, when I tried those ammo using my MP15, they all came out fine. Anybody has any ideas? Thanks
T97 NSR Gen 2 Keyhole with Barnaul 55Gr FMJBT
- Thread starter Ultraviolet
- Start date
M&P15 has a 16 barrel and the T97 has an 18.5. Barnaul's are usually under powered and dirty which is why it is no surprise that it is having problems getting pass those last 2 inches. Stick with American Eagle's. Al Flarherty's sells them for $10 a box and some times when they feel really nice, they are $8 a box. I cleaned them out the last time they were on for $8.lol
Maybe the 1-7 twist is a little much for the 55’s. I would try something heavier. Barnaul is pretty cheap stuff, it’s possible they don’t like the extra spin? Other than that check the flash hider for strikes, and maybe check the bore, some of the gen 1’s had some pretty rough gas port jobs.
A lot of the russian made ammo is under powered.
Some rifles are far more fussy about them.
Most of the 55gr ruski stuff is just well enough to make ARs function.
If it wasn't for the US market, they would have had an even lower standard.
Even then, some brands work in one thing and not another.
Some rifles are far more fussy about them.
Most of the 55gr ruski stuff is just well enough to make ARs function.
If it wasn't for the US market, they would have had an even lower standard.
Even then, some brands work in one thing and not another.
Not all ammo is created equal. Some combos don't get along.
Most 5.56 is probably designed to run a 16" Carbine AR, which can be very forgiving compared to other configurations.
I've had more than one kind of ammo not work well in more that one config.
Just use the ammo that works.
Yeah, sometimes, it's disappointing when you find one of your rifles has expensive tastes.
But then sometimes you get one that loves junk food.
Most 5.56 is probably designed to run a 16" Carbine AR, which can be very forgiving compared to other configurations.
I've had more than one kind of ammo not work well in more that one config.
Just use the ammo that works.
Yeah, sometimes, it's disappointing when you find one of your rifles has expensive tastes.
But then sometimes you get one that loves junk food.
Thanks for the insight!
Thanks, will do
Thanks for the info!
Thanks!
thatmikeguy
Regular
- Location
- Steinbach, Manitoba
Over twisting the bullet doesn't cause keyhole-ing. Under twist does that.
Bubba Yugga
CGN frequent flyer
- Location
- Midwestern Ontario
I know of a gen 2 that does tighter groups with 62 gr XM855 than 55 gr XM193.
A buddy of mine had that happen with an HK SL8 using Barnaul ammo. About 60% of his rounds key holed at 50y. He switched to American made ammo and had no more issues. Some rifles seem to be more sensitive than others to the ammo you feed them, don't ask me why.
Even if the projectiles are defective? Undersized, not concentric or out of round? It is Barnaul after all, they may have even been pulled projectiles. I would think more twist on an unbalanced bullet could cause some issues that may not be as bad at a slower twist.
thatmikeguy
Regular
- Location
- Steinbach, Manitoba
I would suspect 2 things in this scenario. Either a bad barrel or bad bullets. It looks like he proved the barrel good cause he had good results with other ammo. That leaves the latter. I suspect bad bullets.
I have fired 55 grain bullets from a 1:8 twist barrel with beautiful results. I'm not sure what his twist is....think some one mentioned 1:7. Nothing wrong with that.
I doubt a slower twist would make bad bullets shoot well but I've been wrong before. If the bullets are undersized then the rifling won't grip the bullet to spin it and it will tumble.
