Bullet Speed = Gas Check

[brad925]

How fast can i safely push a 405 GR. in a 45-70 before i would be looking at having to have a gas check and what would a good mould be for this?

[Ricochet]

I've shot plain based 405 grain boolits successfully at 1800 FPS or so with 54 grains of 3031 compressed under them. My shoulder thanks me that I no longer do that.

[brad925]

Thanks for the info. I am just learning casting and started by acquiring 300+ lbs. of WW'S. Now i am looking for equipment to cast and all the information i can get from people here as well as from you tube for the visual stuff. I am sure i will have lots of questions to come.

[azrednek]

Brad more than velocity will have to be figured in before you "need" a gas check. The hardness of the lead has to be considered. Do you need a gas check to improve accuracy or to avoid leading? You can get some respectable velocities without a gas check but if you want maximum velocity or accuracy you might or might not need to use gas checks. If you're like me you likely wont be satisfied until you try shooting both in your 45/70. I currently don't have a 45/70, a situation I was hoping to fix this year. I do have a Savage 458 Winnie I shoot cast using 45/70 data. I shoot both plain and gas checked in it. The gas checked shoot a tad more accurately but I'm just punching paper with it anyway so the majority of what I shoot through it are plain based.

[brad925]

I would like to shoot a pointed bullet for hunting. Decent accuracy is a must but i want to try and stay away from leading... at least thats what i have been told in the past.

[Ricochet]

Pointed boolits often aren't the best for hunting. A flat nose destroys more tissue, and casting soft enough to get the pointed boolit to expand often causes other problems getting the load to shoot well at the desired speed.

[wiljen]

I would like to shoot a pointed bullet for hunting. Decent accuracy is a must but i want to try and stay away from leading... at least thats what i have been told in the past.

Pointed bullets are often too long for Lever guns in 45-70 as well as not having as much bearing surface as RN or FN designs and they sometimes suffer from poor accuracy as a result. I think you may find that at 45-70 velocities the spire point does little to help trajectory and is harder to get to feed and shoot well than many RN/FN designs. I'd be tempted to start with the 457643. This is a flat-nose 400gr designed specifically for hunting and use in lever guns.

[Blammer]

:bigsmyl2:if your avoiding GC's because they are expensive, I sell them relatively cheap here at CB.

[Bullshop]

Brad925
Generally pointy cast boolits are very limited in application. That is especially true for hunting unless your hunting very small game.
Its kind of a catch 22 situation in that to make them go fast they must be very hard and if they are hard they will only pierce and leave a very small wound channel that will close behind the boolit and so not bleed out freely. If they are made soft because of the long ogive of a pointed boolit they tend to slump or bend on ignition in the barrel because of the largely unsupported section of the ogive. The ogive is the curve of the nose that begins from the full diameter section and ends at the boolit tip.
A design that is fully supported as in the Guy Luvern design with long parallel sides is much better suited to high pressure/velocity because there is no unsupported section to slump when the ignited powder kicks the bullet into motion. This is all in general information because there are always exceptions but using it as a guide will get you headed in the right direction. If I wanted to use a fairly pointed boolit at fairly high velocity I would look for a design with the Luverin type sides and a very short blunt ogive, such as the LBT spitzer design. The draw back to that is unless you have a very long throated chamber you have to seat the boolits quite deeply in the case.
I use several of Verals spitzer molds in differant calibers and they are very accurate even pushing the pressure up to the top. Not the most aerodynamic of spitzer shapesas far as BC goes but a good strong design.
Something else to look into are previous discussions on soft nose casting. There is certainly a wide open field there.
Best of fortune with your casting!
BIC/BS

[hoosierlogger]

be careful not to use sharply pointed boolits in a tubular magazine (in case you didn't know). You could end up in a heck of a jam, or even the hospital, or worse the morgue.

[brad925]

I will be using cast in my H&R B.C. Will the 457653 mould and #2 Alloy work for hunting.

[stubshaft]

Over the years I have gone from PB boolits to GC bullets because of the latitude they give me in loading. Now don't start a debate on the merits of PB boolits as I know first hand that they shoot every bit as good as a GC design within certain parameters. But, I generally load the same boolit in numerous different guns/calibers ie. 45ACP, 45 Colt, 454 Casull and 460 S&W and when you get to the 30 cal and 458 boolits the list gets even longer. IMHO - gas checks are worth the minimal expense and slightly increased labor to install.

[Bullshop]

Did you mean 457643? You wrote 457653 but I dont see that in the Lyman catalog. If you meant the 643 then I would say yes it will work well for hunting even with #2 alloy which could be considered a fairley hard alloy.
I have used a similarly designed mold from RCBS for many years and have taken all manner of game with it. I used to use quenched WW which is even harder than #2 but now I have settled on ACWW. The #643 is a good design that has been working well for hunting for about a century.
BIC/BS