Month: September 2005

Paper Patching

Posted by on September 10, 2005

While thinking about self reliance I got to thinking about bullets.  That’s not surprising, considering cast bullets is my specialty.  In particular, bullets for BP cartridges.  The limited velocity is compensated for to some extent by weight.  Hence the big calibre heavy bullets in such rifles as the Sharps.  Weight adds momentum and thus allows more range than lighter bullets at the same velocity.  That’s all simple stuff that’s known ( I hope ) by all of us.There are advantages to paper patched bullets.  Moulds are ( relatively ) easy to make.  Moulds are usually cherry cut or lathe bored.  For the amateur there are technical difficulties with both, related to the lube grooves.  Paper patched bullets don’t need lube grooves, so they can be made by drilling and reaming in a lathe.  Aluminium in particular is easily to machine with simple home made reamers.Paper patched bullets can be cast from softer alloy than plain base or gas checked, so they hold together better on impact and provide an element of controlled expansion.

Primers and BP

Posted by on September 8, 2005

If government gets it’s way, there’ll need to be a lot of improvising done to secure arms and ammo in future.  I might have written about primers before but here goes anyway.  Large primers can be substituted for small primers but not the other way round.  It’s not difficult to enlarge a small primer pocket to take a small primer.  Needs a lathe and it’s time consuming, but those will not seem like big problems in an emergency.  About the only things to be cautious about are ejectors striking the primer in auto pistols, but that’s just a matter of checking the dimensions of your pistol.  The other thing might be that chamber pressures might be a little higher.  Wouldn’t be much, would just need the same caution as needed for any change of primer or other component.Why would anyone want to substitute primers ?  Availability.  Might be circumstances when you take what you can get, whether at retail or in informal trade with others.  Also, in a survival situation, it’s a good idea to ensure that all components are interchangeable.  That is, don’t get caught with only small primers when your 308 rifle needs some.  What happens if SAPS takes all your guns ?  You’ll have to get at least one from wherever you can get it.  So you won’t have much choice of what it is, and thus what primer the ammo will need.  Yeah, I know common sense says make sure you’ve got some of everything.  But if you have to make a choice of one primer type only, choose large, at least you’ll be able to use them for any calibre gun you come by.But I do foresee a scenario in which small primers could be used in cases with large primer pockets.  It’s time consuming but not technically difficult to drill and tap a hole in a case head, and machine and solder in a threaded insert with a small primer pocket and flash hole.  Not strong enough for nitro powder, but OK for black powder loads.BP offers other advantages.  Converting berdan cases to boxer is risky because the pockets are bigger.  It was commonly done in the arms embargo days of the seventies but is risky because of leakage.  Lot of guys filled the gap with nail varnish but I wouldn’t risk it.  But BP pressures are so low that the nail varnish trick should work quite well.Centrefire primers are more potent than the old BP primers.  I suspect that a small primer would ignite BP quite well even in a large case.  The low pressure of BP also means pistol primers can be used in rifle cartridges.   Then again I’ve never been entirely convinced that they couldn’t be used in nitro rifle loads.  44 Mag pressures are close to rifle than pistol pressures.  But whatever the arguments about that, it makes no difference with BP.Something I’d like to know is how many BP rounds can be fired before fouling stops it ?  Must be a few, as the Lee Metford 303 loads were compressed BP.  Gas checks work by a scraping action.  Would they be any use in clearing BP fouling ?  Anybody know ?  Anybody care to load a 303 or 458 Win mag with BP and cast bullets to see what happens ?[Originally posted to SATalkGuns]

Gunsmithing

Posted by on September 1, 2005

I have just done a little job which, though small in itself, taught some lessons that might be of use to others.  It was a Tasco variable scope, one of those that has a graduated range drum for quick range setting in silhouette shooting and no doubt other disciplines.The drum is really a sleeve that fits over the steel stem that actually rotates to controls the reticle.   The stem has an annular groove near the top.  The drum has a pointed grub screw in it’s periphery that engages the annular groove, by which means the drum turns the stem.