Am I correct about Barnes all copper ML bullets

[RBDMTJager]

I have HUNDREDS of Barnes all copper .451' 250 grain TMZ and T-MZ's as well as an equal number of .451" 245 grain Spitfires. All shoot great out of my inline ML's wrapped in a sabot.
But I suspect they are likely unsuitable for reloading in my 450 Bushmaster as they do not have the reliefs cut into them like the TTSX and might result in pressure spikes and really bad copper fouling.

Are my suspicions correct or can I reload Barnes ML bullets' in my 450 BM?

[Hoot]

I have HUNDREDS of Barnes all copper .451' 250 grain TMZ and T-MZ's as well as an equal number of .451" 245 grain Spitfires. All shoot great out of my inline ML's wrapped in a sabot.
But I suspect they are likely unsuitable for reloading in my 450 Bushmaster as they do not have the reliefs cut into them like the TTSX and might result in pressure spikes and really bad copper fouling.

Are my suspicions correct or can I reload Barnes ML bullets' in my 450 BM?

It depends somewhat upon how broke in the barrel is. A good barrel, polished by shooting, can resist copper buildup, again somewhat. If you feel like an experiment, plate some of those with either HBN, MoS2 or WS2, in that order of (my) preference. I plate all of my bottleneck bullets with HBN. Cleanup is a breeze. And besides, the .452 diameter 250gr FTX is pretty popular with the same degree (perhaps greater) of exposed copper. I have shot HBN plated bullets in my 450b. You give up a small amount of velocity due to lower pressure but you can offset that by using a slightly higher powder charge.

Hoot

[Al in Mi]

I've shot 25-30 of the 250gr TEZ's from my #1 Ruger, just as accurate as its pet 270gr TSX load. Didn't notice any more fouling but this gin is pretty forgiving.

[pwee223]

The .451 250 Grain Barnes are Killing bullets. Don't let 1,000thhs. deter you.

I have proof. LOL

[coyote wacker]

One thing to remember is the Old Barnes all copper bullets didn't have the bands cut in them....higher pressure with a lower powder charge...I had several guns that just didn't like them but shot the new Barnes with band much better .....the bands were put to releave pressure the bullet will have less friction....Barnes all copper bullets tend to be "sticky" when compared to many other bullets....
Most people don't know that Barnes bullets are not CNC lathe turned bullets....but punched out so there is a size difference from one to the next....that is why they are cheeper than CNC type bullets....

[Al in Mi]

those first smooth sided Barnes were horrible for for copper fouling even in custom lapped barrels. When that first bit of copper stuck, it acted like a cheese grater for every bullet going over it. Once they added the bands it minimized fouling considerably, dunno if it was the bands or a change of alloy or added a heat treat, but is way less today than it was. I never had a fouling issue with the smooth sided ML bullets in the 450 thou, so something changed or I was just lucky.

also, don't worry about them being .001 smaller, when the big light hits, they will bump up to full groove diameter. I've shot plenty of the .451's in my smokeless ML's that were bore sized and they bumped up to take the rifling on a .458 barrel.

[Hoot]

Smooth sided monolithic bullets don't obdurate nearly as easily as cup and core sided ones, so there's more smush against the bore to rub off the copper. I seem to recall that Barnes changed their copper alloy blend a while back to make them less soft. That alone would improve how they ride, not to mention the driving band grooves. There's always plating then with MoS2 or HBN. HBN plating sure makes cleaning my bottleneck calibers a lot easier.

Hoot

[Al in Mi]

forgot to add, Barnes did try to address that fouling issue back then with a baked on Smurf blue coating of some sorts, but I had already swore them off and never tried them.

I think Bear Creek uses HBN on their bullets. I haven't shot enough of them to have a opinion yet.

[teddy_d]

I've used the TMZ-BT 250 grain in my AR, I have not experienced any copper fouling in my AR.
I also have not witnessed any over pressure signs with LilGun.
Accuracy has been more than acceptable.
Longest shot 242 yards, no problem with terminal performance on a very large Doe.
Much better trajectory than any other bullet I've tried out to 300 yards, even in cross winds of 20-25mph. I don't believe any of the printed information about trajectory, its only a basic guide imho. Shoot your gun at measured distances and log that data!

Granted I've shot less than 100 rounds of these.