Open letter to CVA Paramount and MRX 1-22 twist rifles

[700motherlover]

Ive got one barrel that has massive bulging from an off powder bullet. Its visible to the naked eye inside the barrel but nearly undetectable from the outside. I think it might burst if a couple more short start bullets get fired thru it.

Sounds like bad steel, make and model?

 

[michiganmuzzy]

Sounds like bad steel, make and model?

Green Mountain barrel Knight disc

 

[Oldranger]

I fell for the ELR hype. New 45 MR-X.
It bothered me that cva didn't mention the ELR for Accura just the Paramount.
But they make a 45 ELR. Big mistake.
They don't shoot, and it's not me. So I slugged the barrel. My Mitutoyo and my
RCBS both read 0.461. The ELR's are 0.449 and without the plastic they fall out of the barrel and don't make a sound. The plastic bases come off easily with a slight twist.
Not a good situation.

 

[GM54-120]

RCBS both read 0.461

Your lands or your grooves are .461?

 

[michiganmuzzy]

Maybe the qla muzzle measures 0.461? But not the actual bore?

 

[Oldranger]

I'm no expert. You tell me. I have some .482 round balls. I oiled the barrel and the ball. Tapped it lightly with a small hammer, into the muzzle. Then tapped it lightly with 4 sections of dow rod until it exited the breech. I measured the lands that were 180 degrees apart, then rotated the bullet to the next set of lands. All measurements were .4605 or .461.

 

[HC]

That was the groove of the barrel. The diameter of the groove in the slug is land diameter.

 

[Oldranger]

ok. I measured the widest part of the bullet.

 

[michiganmuzzy]

Measure the narrowest part of the bullet.

 

[Oldranger]

.457

 

[michiganmuzzy]

Thats your lands. Your bullets ought to be that big. Or maybe .001-.003 larger depends on their construction; lead, jacketed or solid copper.
I wish that was smaller, like .451-.453

 

[Oldranger]

Ok . So .449 bullet for .458 to .460.
Seems like a lot of swelling needed.

 

[michiganmuzzy]

Yeah thats a lot. On the plus side you are real close and may be able to shoot .458 bullets. There are lots available. Or switch to sabots and .40 bullets.

 

[GM54-120]

Plain old 250gr XTP is .452+.......got any laying around to see if it free falls like the PB?

 

[Oldranger]

Good idea. I found some Shockwaves that I used saboted in my Encore 50.
They measure .4515 and completely free fall thru like the 449 ELR's.

 

[Oldranger]

With my barrel numbers of .457 and .461, would a .453 Fury be a possibility?

 

[Pathfinder60]

With my barrel numbers of .457 and .461, would a .453 Fury be a possibility?

Possibly. I'd recommend knurling them up between two fresh bastard files if they prove to be too loose. The 265gr STBs prepped in this fashion are what I have shot out of my Paramount with reasonable success.

 

[jsteurrys]

Smoothing forming 0.458" bullets might work for your barrel.

 

[rickiesrevenge]

Man, sounds like I dodged a bullet on this one. I was looking at paramounts but didn't find any in stock.

 

[GM54-120]

I would not tollerate a bore being that far out of spec. They would be giving me my money back.