Meplat Specifics for design

[458Scout]

I have a Marlin 1894 Cowboy in 45 Colt. I've used a vast variety of bullet designs, weights and powders.

Most are very good but I just have to design my own mould. I was leaning towards a more rounded nose
and am wondering, if there is a specific ruling on meplat diameter? The 45 Colt uses a large pistol primer
measuring .2095. Obviously the meplat must be larger to prevent magazine tube detonation.

I was thinking somewhere around .254

Any suggestions?

[jmort]

If you are just punching paper, then it is not critical. .254 seems small to me. My .357s have .270/.280 meplats. The Lee Precision .452 300 RF would be a good design to copy. If you are determined to go small, check out the Accurate mold catalog for some ideas. There is no reason a .254" meplat would not work.

[runfiverun]

unless you are concerned about oal for some reason.
like feeding through a lever gun or having a cylinder that rotates.
or wanna use the boolit to hunt with..

[Bigslug]

Accurate Molds 45-255C should solve your problem. After 140 years, you're unlikely to tread much new ground with a custom mold for that round. Might want to cast a large net over the various makers to see what your options are first.

[Harter66]

I have a SWC with a 35? meplat it doesn't seem to stay stable in the 92' but is fine in a RBH . 452-252. The 452-255 RNFP seems to shoot better but the meplat is under 300 on it.

[DougGuy]

Lots of people favor the wide meplat designs because they do horrendous damage on game and they add weight to the boolit which also helps do horrendous damage, even if the said game is standing behind a tree it will do horrendous damage to the tree and still take the game.. Sometimes, things work very well for a reason, and as was mentioned earlier, it's hard to improve upon something that after 140yrs of being in the company of those with fairly gifted levels of intelligence have brought it to the point that no further improvement is needed, nor is there any remaining room for such.

Lee C452-300-RF boolit. For a levergun, it may need to be seated in the upper crimp groove, but this is one that has earned it's keep with many on this forum, there is also an improved mold for this boolit in group buys which has deeper crimp grooves and a better fitting gas check shank. Again, about as improved as you could want.. Meplat is .380" or thereabouts.

http://i1202.photobucket.com/albums/bb374/DougGuy/Reloading/b0365352-e008-4573-ae2e-859b8a99fe82_zps7c72c5cb.jpg (http://s1202.photobucket.com/user/DougGuy/media/Reloading/b0365352-e008-4573-ae2e-859b8a99fe82_zps7c72c5cb.jpg.html)

[Gtek]

I think I remember reading Mr. Keith stating that a meplat of 70% was the diameter he prefered for life force removal. As stated above, hard to beat those that had the time, ability, recources to four lane, pave and landscape the trail of over a century ago. Many proven designs to choose from, my quest is usually that couple thousandths for fit.