Brent
(.224 member)
12/02/06 05:38 PM
Re: 577-450 dies needed

DD,

Some interesting stuff there. I realize that it will take some experimentation to work up a load - ever new rifle does.

I take it that Magtech and CBC is one in the same. I have ruled out that brass for another reason just a minute ago. Meanhwile, I wouldn't use Bertram on a bet, and I don't know where to find Kynoch, so that leaves RMC turned brass. So far as what I know about available brass. That can solve all the head space/rim-thickness/head-thickness issues in one shot as they can be turned to match a chamber casting.

I'm quite aware that Martini bores are not standardized. I can deal with most or all of that with paper patching, but if a new mold is required, then so be it. I would never ever shoot a .458 bullet in any modern .45 caliber anyway. The bore will be slugged before the last packing material hits the floor when it arrives.

Your comments on compression make me a bit curious. Necked cartridges can be compressed though that may bring powder levels above the shoulder. I don't see that as a problem. I am curious why you think this would be an overload. I have read about people taking apart original compressed 577/450 cartridges. compress of bp is commonplace in other necked cartridges. Perhaps the severity of the shoulder is the reason? That still doesn't solve the question of original cartridges with compressed loads. Is the Martini action particularly weak that it cannot handle a heavier charge?

1fg Swiss of some batches, and most especially the first batch that was brought over, is far more extreme than 1.5fg or Goex Cart or 2fg in many (all?) more recent batches. Hence, I really don't like to even think about bounding load safety issues on the bases of XX amount of manufacture Y's, Z FG granulation. 85 gr of Swiss 1.fg has so much variation across batches that I find it rather difficult to say anything especially definitive about any particular loading as being best, or maximal, or safe or whatever. Can you give me a good idea of what you feel would be a maximum safe velocity for a given weight bullet? (I'm thinking of about 500 grs or a bit heavier). I understand that different speeds of powder will produce different pressures for a given velocity, but it's probably a better approximation than a powder/granulation weight.

I didn't see much on the Martini resources website about reloading except for a link to my own webpages and Coydog's. If there is anything specific to the .577/450 I sure would like to dig it out.

Thanks again,
Brent



Contact Us NitroExpress.com

Powered by UBB.threads™ 6.5.5


Home | Ezine | Forums | Links | Contact


Copyright 2003 to 2011 - all rights reserved