Old Fa** still learning 45/70 keyholes

[mpmarty]

I've had a Marlin 1895 for over twenty years. It has the "modified micro groove" rifling and has never shot my cast gas checked bullets worth a darn. Gave up and quit shooting it other than once in a while with Jboolits on deer and bear.

Playing around with my molds and came across the old ideal 405gr flat point and decided to cast a few for old times sake. Cast twenty five very nice lightly frosted sharp edged boolits. Don't have a lee sizer setup for this cal so I went looking in the old storage bins for my Lyman lubrisizer. Got it out and put in the 459 sizer die and top punch and found my gas checks.

Ran two boolits through the sizer, seated gas checks and lubed the bottom two grooves. When I quit using this boolit many years ago, I blamed the rifling for the poor performance. Today, I used my digital micrometer and measured the sized gas checked boolits. Lo and behold!! .454 to .456 WOW!!

I just went on line and ordered a Lee sizer setup in the only size they have that's close to what I want (.459) and it's a .457. Can I "polish" this out a couple of thousandths of an inch? How?

[Freightman]

Do a search and it is spelled out how to increase the Lee sizer.

[44man]

What does the boolit measure as cast? You will be hard pressed to get a Lyman to cast large enough to use a .459" size die. Have you shot them without sizing?
If your boolits are large enough you can run the base into a .459 size die just enough to crimp the checks, leave the rest of the boolit alone and lube it by hand.
You can't size a .457" boolit in a .459" die. Can't crimp checks either.

[mpmarty]

As cast they are .459 - .460 I've tumble lubed them and will try them without gas checks until my lee sizer gets here, then I may try to shove them base first into the .457 sizer enough to crimp on the checks and then knock them back out with a drift and mallet. Thanks for the replies.

[jack19512]

I'm sure you already know this but I have never had to use the gas checks in my Marlin 45/70. I use the Lee 340gr. and the Lee 405 gr. plain base boolits and get real good accuracy. Using the gas checks when you don't have to only adds to the cost of your boolits.

[Gerry N.]

For 25 bucks, Lee will make up a sizer in any diameter you wish.

Gerry N.

[HangFireW8]

Ran two boolits through the sizer, seated gas checks and lubed the bottom two grooves. When I quit using this boolit many years ago, I blamed the rifling for the poor performance. Today, I used my digital micrometer and measured the sized gas checked boolits. Lo and behold!! .454 to .456 WOW!!

I just went on line and ordered a Lee sizer setup in the only size they have that's close to what I want (.459) and it's a .457. Can I "polish" this out a couple of thousandths of an inch? How?

Ranch Dog molds stocks and sells special-order versions of Lee molds and sizers, including .460" for 45/70 micro-grooves. I am considering getting some myself, but I want to shake out the equipment I have first before jumping into more.

http://www.ranchdogmolds.com/

-HF

[Dan Cash]

Pan lube and shoot as cast.

[35remington]

Undersized cast bullets - especially really undersized cast bullets - will often keyhole, and will certainly shoot very poorly.

My microgroove Marlin 45-70 is a tackdriver with cast bullets.

[jack19512]

My microgroove Marlin 45-70 is a tackdriver with cast bullets.







Do you use the gas checks with your boolits or do you use the plain base boolits like I do? I'm just curious if your Marlin 45/70 does as well as mine does without the checks. I don't think I could ask more of mine when it comes to accuracy but you never know I might be missing out on something here.

[mpmarty]

Thanks a bunch. I had no idea RD had six cavity molds for 45/70 I'm gonna get me some of that sweet stuff. Unfortunately, he's out of .460 sizers for a couple of months yet.

[HangFireW8]

Thanks a bunch. I had no idea RD had six cavity molds for 45/70 I'm gonna get me some of that sweet stuff. Unfortunately, he's out of .460 sizers for a couple of months yet.

No problem. :)

-HF