Assuming you knew your bores dimensions and rate of twist, how would you go about selecting a bullet mould for a specific cartridge? 
  
This would be for ASSRA-style 200 yard match shooting.

Would you use a different bullet for breechseating that you would choose for shooting as fixed ammo.

IN my specific situation I have recently acquired a custom single shot in 8.15x 46r,   I have cases dies etce etc, a significant quantity of 4759.  I have the 180 gr stop ring bullet mould Buffalo arms sells. but I'm interested in a more conventional bullet for breach seating.  

There is such a plethora of bullets in use----even just at the EG range---custom designs from custom makers as well as old antique moulds, designs, and bullets that I sort of figure that much of the selection is based on qualitative rather than quantitative criteria. 
I'm wondering if anyone has figured out a semi-rational efficient method for arriving at a starting mould choice?
I know that with the EG range wind conditions, that stability, using a long/heavy for bore size BC ratio bullet might work better and that slightly tapered bullets breech more easily.   But other than that is seems pretty much a crap-shoot to me.

I've studied bullets for BSing for 28 years. The ones that do best are tappered. They do best (IMO) is because they BS with less distortion.

The successful tappered bullets have the nose at close to bore diameter with the first band .001 - .003 larger than bore dia. and increasing at various increaments to anywhere from groove size to as much as .003 over groove dia. i.e. In a 32 caliber (.315 bore, .321 groove) 6 band bullet, the first 2 bands might be .317, the next 2 .319, fifth .321, base band .322/.323 or they could have a straight tapper from .316 to .322 base band or, anywhere inbetween. The key is getting the first band started inline with the bore and the rest of the bands to follow with the base band sealing the groove. The less tapper the greater the force that it takes to BS the bullet and  the more distortion can occure.

The things that your looking for where BSed or fixed is to get the bullet into the barrel straight and undistorted. Stop ring bullets maybe traditional for European Schuetzen rifles but, getting that stop ring swaged down  (even if the fore part of the bullet fits the rifling) to groove dia. while the rear of the bullet is unsupported, can't be the best thing to do. Some of the stop rings are as much as .010 - .015 over groove size. I think a good fitting bore riding bullet would be better for fixed and they will shoot well BSed, too.

The bad thing about the 8.15x46R is the groove size runs between .314 and .321 and I've seen very few .321 grooved rifles. More common is the + - .316 (mine is .303 bore/.316 groove) so, molds are hard to come by. I use the 1.05 long 311413 that casts .303 at the nose and .313 on the bands in 25/1 and I reamed the GC to a .318 base band.

Frank

Agree with everything Frank said,........ except, in my .316 GD German barrel, a .321 tapered bullet shoots best with no leading. Same with stop ring bullets loaded fixed. (lead bullets).

Have found with my rifle that if a lead bullet fits close in a fired case neck, it will shoot accurate with no leading. My rifle has the early version 8.15X46R chamber. 

       Joe. 

If your groove diameter is .321, use tapered Pope style bullets. The Saeco 32 molds are very good for the price. 

My method to find the best bullet in a given rifle is to try a lot of different bullets till you find one that works best.
Never liked making rocket science out of it. Tapered bullets have always worked best for me. 

      Joe. 

I know of at least one shooter who was building his rifle with a standard .32 cal barrel and chambering it with an 8.15 X 46R reamer.  You'll really have to slug that bore.

Regards, Joe

QuestionableMaynard8130 wrote on Jul 20^th, 2013 at 9:31am:


Hi,

Everyone who has responded has given excellent advice.  One can't go far wrong with a conservative design as long as the bullet is the proper length (and weight) for the rifle's twist rate.

A conservative design is similar to the David Mos "Standard" bullet, which is a slightly tapered, five band bullet with an approximate 3R ogive.

For a 14 twist, .320/.312, six-groove  Shilen barrel, my bullet is .3225" on the base band and tapers to .3180" at the base of the ogive.  It casts at 211 grains using 20/1 alloy. 

While it lacks the panache of a 6R spitzer, it remains an elegant, reliable design.

JackHughs

There is really no "magic" to match grade bullets. Barrels and bullets are a product of dimensions (even with Pope and Smith barrels). Good barrels (meaning undamaged and straight), mounted w/o external incumberance (as in Ruger) and good quality (well cast) tapered bullets will shoot well. As long as you match the throat to the base band (seal) and get the BSing depth right.

Frank

I don't disagree with you in taking accuracy to the highest level but, Wayne was asking about how to select a bullet that would supply accuracy and not the load behind it or how to improve his shooting skills. I believe he wants to just buy one bullet mold that he can develope into a competive combination instead of buying this mold or that and then shelving them to buy yet another one.

As for bullets, it's better to get one that will "fit" the barrel to start with so you can have more confidence to starting your load developement. 

It's much easier and cheaper to buy powder, primers, lube and alloy than buy a custom mold.

Frank