Copper Bullet characteristics

[El Chivo]

I recently wrote Barnes and got a reply from Ty over there, plus I read some of the FAQ's on their site. It got me thinking about the nature of the copper bullets that might give us some insight for loading them.

The Barnes site says it's not necessary to crimp into the grooves. You can seat the bullet anywhere it works. They suggest .050" off the lands at least.

Ty told me to crimp lightly into the first groove (30-30) because of the intended use in the tubular magazine. But the crimp is not to build up pressure, it's to prevent telescoping in the mag.

Reading on, they say there's less pressure buildup than with lead bullets. So you can/should load more powder. This reminds me of some of the comments from guys who tried moly-coated bullets. The moly made for less friction, there was less pressure buildup before release, so velocities were lower. To me the copper bullets feel like they would have lower friction than lead. That makes sense, but I was thinking the opposite, and I was a little worried about high pressures.

The way the bullets work, they remind me of those broadhead arrows that fan out on impact, rather than the deadliest mushroom in the woods. It seems very efficient the way those blades extend, and so effectiveness might not be a function of bullet weight as it is with lead.

I'm thinking of it as a blade that cuts rather than a projectile that hammers its way through. Ty mentioned the 35 Rem would not give the velocity to open the blades properly, that is counter to the big, slow bullet idea that works so well with lead. High velocity makes it expand immediately at the hide, then it cuts its way through like a daisy wheel.

Anyway, I want to throw this out for discussion, so we can all benefit.

[Old Time Hunter]

That is pretty much why a .223 opens and stops before it gets thru the tree and a .45-70 keeps on motoring. The copper jacketed .223 expends it's energy trying to expand, the .45-70 retains enough energy to continue forward motion. In theory the .223 has quite a bit higher energy level coming out of the barrel at 3k+ fps, but it does not have the follow thru energy. The copper (never heard of a lead .223) is required to maintain the aerodynamics of the projectile and allow for planned expansion that allows the use of a smaller projectile to make as large of an entrance wound as a larger projectile, just doesn't go as deep.

[Andrew]

The way the bullets work, they remind me of those broadhead arrows that fan out on impact, rather than the deadliest mushroom in the woods. It seems very efficient the way those blades extend, and so effectiveness might not be a function of bullet weight as it is with lead.

I'm thinking of it as a blade that cuts rather than a projectile that hammers its way through. Ty mentioned the 35 Rem would not give the velocity to open the blades properly, that is counter to the big, slow bullet idea that works so well with lead. High velocity makes it expand immediately at the hide, then it cuts its way through like a daisy wheel.

Are you talking about their "X" bullets? I believe you are 100% correct about the function of them. From what I have read, they do exactly that and afford deep penetration and one heck of a bloody trail along the way. If I am not mistaken they are very useful for larger game that take a hard projectile to get deep to the vitals. Better yet, make a clean pass all the way through and leave a nice "leak hole" on the oppisite side.

[TomD]

"I'm thinking of it as a blade that cuts rather than a projectile that hammers"

I doubt that. They by all accounts kill really well, but a cutting wound is a very different thing, some good things some bad. For example, while modern practice would dictate a much heavier bow, elephant have been killed with recurve bows in the 70 pound range. Same bow would work on rabbits, would kill a deer with authority, a moose, and so forth. You just don't get that kind of result with rifles though the comparison is probably closer with solids than with any bulelt that expands.

[shawn_c992001]

Alot of the penetration of the X-Bullet has to do with the solid copper back half of the bullet. If the bullet does shed it's pedals it still has the back end that continues on it's forward path, the Nosler Partition shares the same potential.

[Marc]

My wife and I have killed 25 to 30 deer with X-bullets. I am not sure what you are looking for? I use a 264 Win Mag and the wife uses a 6mm Rem. I have never recovered a 264 bullet. They always pass through no matter what angle they hit or what bone they hit. We have recovered three 6mm bullets(90 grain). Two traveled from stem to stern and lodged in the hindquarter. These bullets start at .244". They expanded to .520" to .530". You put one of these in the boiler room and you have a dead deer! They will break shoulders and pass through. The other recovered bullet was a finishing shot into the neck and it lost all the petals and lodged in the vertebra. It did its job.

As far as seating depth, the 6mm has a long throat and you can't get anywhere near the lands if you need to feed from the magazine so I never bothered measuring how far they are off the lands. The .264 has an oversize bore at the throat . Groove diameter is .2655". Bullet diameter is .2635". I seat them just off the lands and they work great. I think I get away with seating them close to the lands because the bore is oversize. So once again it comes down to individual rifle differences.

The penetration comes from weight retention. The wound channels tends to be smaller than a jacketed bullet makes and so there is also less bloodshot and wasted meat. I like 'em and I like 'em a lot!

[CJM]

The powder difference is due to the copper bullets being lighter than lead bullets; it's not a difference in friction, lead has less friction against steel than copper. Lighter bullets leave the case sooner and accelerate faster, so you can use more powder behind them.