300 SMK bullet Jacket Separation BA 110 338 Lapua

I've posted my adventures with this BA 110 in a few posts here.

Just posted my results of a 2000 yard competition in the Range Report forum. What i left out of that post is an issue regarding jacket separation.

During this match i experienced 3 bullet failures. It was pointed out by my spotter as I was the new guy shooting solo. With my hearing protection I didn't hear the distinctive sound a bullet makes when coming apart.

These bullets are from a single 500 count box.

I have fired approx 200 of these at 50 , 100, and 1000 yards this summer. I'm wondering now (prior to this competition) if some of my local range 1000 yard misses or unseen splashes were in fact bullet failures.

After this competition I have experienced 3 additional jacket failures out of 60 shots.

My plan is to shoot my 250 SMK loads to see if I experience any jacket failures.

Mike

id call the guys at sierra and ask what they think...real nice guys there and very helpful.

No where near enough info to help you.
Define "bullet failures". Over spinning leads to instantaneous destruction, so tell us about your rifle and loads, have you checked the ports on the brake? Velocity, twist, conditions, etc.

Twist rate 1 in 9
Speed 2750 - 2800 fps
Brake is undamaged

as for the 'failures'..... There is a distinctive pop sound with the bullet failing to reach target zone/area. Last time shooting I had 2 failures. I was shooting at 1000 yard steel and was able to see thru scope the bullet impacting the dirt about 300 yards from me.

Maybe there is a bur in the rifling. Near the crown or something. Causing it to possibly cut a deeper groove in the jacket before leaving barrel.

Just returned from range.

fired 25 rounds of:

250 SMK
H4831sc 87 grains
2850 fps

No jacket separations

That's just over 215,000 RPM. Not near fast enough for jacket destruction.
But I question a 338 LM being able to see impact at 300..

Darkker,

Yes, I agree the rotation and velocity are normal.

Yet, I've experienced 6 jacket failures (that i could hear/see). It's possible I had other failures before the 2000 yard competition that i did not realize occurred as I shoot without a spotter at my local range.

Of the 6 failures I 'heard', I just caught a glimpse of 1 impacting the ground/dirt approx 300 yards out from the shooting bench. I'm only guessing at the distance.. it could have been 200 yards.

Mike

It strikes me more of a off kilter bullet in the lands. As though the bullet is of center when it engages the lands, that will assure rapid upset.

Here's an something i discovered today while loading 250 Scenar.

Occasionally, I would feel resistance AFTER seating the bullet while LOWERING the ram with completed cartridge. So I disassembled the RCBS Gold Bullet Seater and discovered some sort of blemish inside the bullet seater.

Here's a pic

http://i181.photobucket.com/albums/x...t%20Seater.jpg

http://i181.photobucket.com/albums/x...S%20Seater.jpg

Update: Sept 29th

Fired 52 rounds today at 1000 yards.

10 loaded 250grain Lapua Scenar with 103.5 grains RE33

42 loaded 250grain Lapua Scenar with 87 grains H4831sc

ALL 250 Scenar bullets fired normally without any malfunctions.

Summary:

300 SMK - 6 'failures' out of 114. Powder used = RE33 and IMR 7977
250 SMK - 0 'failures' out of 25. Powder used = H4831sc
250 Scenar - 0 'failures' out of 52. Powder used = H4831sc and RE33

Mike