Keyholing 55gr

[Hoss]

Hello all, maybe you can help me with an issue I had today. I was attempting to zero in my AR and had severe keyholing at 50 yards. The target literally has holes that look like the bullet impacted sideways.

Rifle: Bushmaster XM-15 E2s with a 14.5" barrel 1/9 twist
Ammo: Monarch 55gr fmj

 

[freedom]

Take the flash hider off and see if it still does it.

I've see a bunch of crud built up inside those things before.

Have you tried another brand of ammo?

 

[Gunsite Grad]

Subscribed because I'm actually curious

 

[Hoss]

Take the flash hider off and see if it still does it.

I've see a bunch of crud built up inside those things before.

Have you tried another brand of ammo?

Flash hider is pinned since the barrel is only 14.5" without it. I haven't tried any other amm, I only have two types right now, both Monarch 55gr. I can the 55gr HP's and see if they do it as well. Accuracy is all over the place with it keyholing like this.

 

[freedom]

Can you see any damage to the crown?

Can you see any build up down there?

A little bit of obstruction can cause the gases to exit the barrel unevenly. If the gas isn't coming out equally all the way around the exiting bullet it can/will keyhole.

It's got to be something at the end of the barrel.

 

[EugenFJR]

I had a bad lot of cheep ass Silver Bear ammo do the same thing to me... Get some new ammo, if it all key holes, then it the BBL.

 

[Hoss]

I opened up a box of the 55gr HP's and shot 20 rounds. At 40 yards I had no keyholing. I guess the fmj 55gr monarch I got is shit.

 

[EugenFJR]

I opened up a box of the 55gr HP's and shot 20 rounds. At 40 yards I had no keyholing. I guess the fmj 55gr monarch I got is shit.

It happens...

 

[Laufen]

Monarch is garbage, and if some care isn't taken with hps, lack of jacket thickness uniformity will fuck with bullet stabilization. I'll bet your rifle is fine, shit ammo.

 

[NWS]

Rifle is probably junk. I'll trade you for a 1/7 carbine.

 

[boss_hawg]

what year / city and state is the bushmaster?

if lower says windham, maine then your ammo is crap. if lower says anything else then your rifle and your ammo are crap. sell all of them and buy a noveske. /thread

 

[NWS]

what year / city and state is the bushmaster?

if lower says windham, maine then your ammo is crap. if lower says anything else then your rifle and your ammo are crap. sell all of them and buy a noveske. /thread

It is an old Windham Bushy

 

[boss_hawg]

It is an old Windham Bushy

ur ammo iz p00p

 

[sewerman68]

I've had steel cased 5.56 ammo that had been loaded with 5.45 projectiles. Accuracy was shit.

 

[Hoss]

I've had steel cased 5.56 ammo that had been loaded with 5.45 projectiles. Accuracy was shit.

Hmmm, I'll do a barrel check. Thanks