Pairing Solids and HP's of the same weight? or not?

[wonderwolf]

With so many adjustable mold group buys going on I've had this pondering floating around in my brain a fair amount. This is more of a rifle question as I'm thinking as most of us tend to carry one load in a wheel gun/revolver and know where that one load prints at longer ranges, whereas we may not mix loads in practice afield for longer shots. But for rifle it may be desired to carry a solid and a hollow point option. Combat stacking isn't my idea here but it falls in line with what I'm pondering.

Say we have a 30/06 that we have zeroed for 150gr Lee flat point bullets and we want a hallow point cast that will duplicate the zero already established. If we took the same 150gr design and just made it a hollow point (say a 120gr HP) the impact would be lower at moderate ranges(most of the time, in theory). But if we took a 180gr mold of the same design and made it into a 150gr HP mold (same bearing surface) I'm thinking it should print pretty close if not the same to the original solid load. Right?

I understand bullet OAL does play a factor in this but I'm not sure how if the weight is the same between the solid (shorter) and the HP (longer) with both having the same bearing surface (same pressure). I've been reading Rinkers book on "Understanding Ballistics" as generously donated by a forum member and its left me to the conclusion that well....simply put I need more molds if I'm to have rifles that print the same with solids and hollow points of the same general design.

[Wayne Smith]

Theory is great but you really don't know until you try it in your rifle. Depending on the cartridge and the rifle there may not be a lot of difference in 100yds (say 30-30) while you will see much more dispersion at 300yds (30-06). So you need to determine typical range as well as how your rifle does with your boolits. Get a double cavity of a good design and have Eric HP one of them. At the very least you will have two boolits with a specific difference, and they may be closer than you think.

I don't know this but I'd be willing to bet my 457122 Gould mold, made without the HP, and made with the HP, will be within an inch or so of each other at 100yds.

[MT Gianni]

Typical weight for a 150 gr hp'd would be around 137-140. Minimal difference in impact point at 100 yards.

[wonderwolf]

Typical weight for a 150 gr hp'd would be around 137-140. Minimal difference in impact point at 100 yards.

I'm thinking of buying a Lee 170gr FP and making it into a HP mold, turn and tune a plug to get me at the same dry weight as the as cast 150's. I'm thinking the 170gr has a little more bearing surface. I'll play with the 150 I have now and maybe HP it as well and see if that really matters.

It would be easy if this were just for one rifle however I'm trying to figure out what is best practice in bullet selection across several platforms for .308 & .30/06

[Wayne Smith]

Remember that a boolit design optimized for the -06 will not be optimized for the 308 - neck length issues.

[nagantguy]

had this same question a few years back when was doing Lots of bear hunting, the 168 gr load in Mr dead, my favorite worked over built up go to rifle in 06, keep in mind j words not cast but I went with a 180gr load for bear, and at 100 yards thereally was almost no diffrence in point of impact! so I took.this to cast in my 30 30 and 45acp, lighter hpd boolits for vermin and plinking, same powder charge or very close and oddly enough the 30 30 hps where just slightly lower less than .5 inches and the lighter 45acp boolits we're slightly higher and seemed to group with a little left of center, talking an inch or so.