Wednesday, January 23, 2013

I'm back, and will be posting test results from some custom molds.


I haven't been able to post for some time as work has been crazy.  That's good, not having work would be tough.  Anyway, I've been testing a cutomer 145 grain round nose / flat point bullet in revolvers and lever action rifle.  I also have a 168 grain version to discuss too.

I'll refer to these as my first generation custom molds.  I went through several designs and found some noses that worked and some that didn't.  In the near future I'll cover the good and the bad.  I already have orders placed for generation 2, or Version 2.0.

The question is, what is the optimum bullet size for a 357 magnum rifle, in this case the Rossi.  It has a slow 30 inch twist, which like lighter bullets.  Then what is the optimum bullet size for 357 magnum revolver, something in the 16 to 16.5 inch twist range.  Which likes heavier bullets, with high velocity.

The answer I came to is that the 140-150 grain range would provide the shorter length that the rifle would like.  It also turned out to work really well in the revolver. 

Here is the bullet, which exits the rifle barrel at 1,850 FPS, and the six inch revolver at 1,400 FPS.  It's a little hot for the handgun so I don't shoot it often.  In the rifle, this bullet has more energy at 100 and 200 yards than a 125 or a 158 grain bullet.  With a gas check, it is a sweet hard hitting shooter.  Accuracy is very good, but not stellar.  So 2 MOA at 100 yards is very repeatable, but more about that in the next update.

For now, heres the 145, I'll post more soon:

4 comments:

  1. Remember, twist rate favors different "length" bullets, and not necessarily weight.

    Also, my personal opinion is that gas checks aren't needed in .357mag. You may have to dork around with the correct hardness/size, but a flat base with correct obturation will prevent gas cutting.

    (I just finished reading a book on Elmer Keith's work. Pardon me if I sound snarky)

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    Replies
    1. Hi,
      Technically you are correct about twist rates. If you look back at prior posts I actually do mention that fact it's really about lenght. However for a given nose and lube groove configuration, a longer bullet will weigh more.

      It becomes tedious to have to type that in every time twist rates are metioned, so I don't. I expect the reader to understand that.

      Handloaders do find it more helpful and informative if I mention a 145 RF vs a 173 SWC. Talking to .580 inches and .744 inches just isn't helpful. Again, it gets tedious to mention both weith and length every time, unless the article of post is specifially on the subject of twist rates and bullet design.

      As you know, I'm a fan of the 358429 bullet. Elmer Keith didn't like gas checks in 357 or 44 magnums. At least in revolvers. However he's not the only accomplished bullet designer. Check out some of the info regarding Ray Thompson http://www.americanhandgunner.com/to-check-or-not-to-check/ who created the 358156. It's a gas checked bullet for the 357 that many consider the best design for my favorite caliber. Also Skeeter Skelton wrote some great articles, he has pet recipes for both the 358429 and the 358156.

      I have found in lever rifles, that gas checks really extend or raise the usable velocity. I get a very accurate 1,850FPS with a 145 RF design with a gas check. Without a check, the accuracy falls off after 1,500 FPS. That's a significant difference. It's worthy of a gas check.

      You and many others choose to not use gas checks in a 357. There are others that use the Thompson design and use them all the time. I have no problem either way.

      This turned out to be really long, so I may actualy make this a post in the near future.

      I have no issue with you having your opinion. Just don't expect everyone to agree, espcially when there someone like Ray Thompson who's designs are outstanding.

      If you don't believe me, just Google away.

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  2. I don't think anything either of us said was incorrect.

    Personally, I have not hand loaded for a .357 rifle, so my context is limited to revolver shooting. Also, I certainly wouldn't say G.C. don't help. I realize at higher velocities there's a benefit. For me, the bulk of my hand loads are geared for training and/or plinking, where I'm stingy on powder - peak velocity isn't a concern there.

    In my previous post, I called out that I was in a snarky mood, but I'm sorry if you didn't pick up on that.

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