45-70 loads, at what Pressure do I need to start using Gas Checks

[TMenezes]

Hi guys, I love my 45-70 but to date I have only loaded low pressure loads. I want to make some more powerful loads for hunting. I don't really want to bother with Gas Checks unless I absolutely have to so just wondering at what pressure they start becoming necessary. My lead is fairly soft, mostly scrap from the local recycler with enough Lyman #2 thrown in to harden it up a bit.

Right now I mostly use the Lee mold that's 340gr or so but looking at the 405gr and 450gr molds. I'm looking at data that's rated at 28k psi. I saw the data that's up to 40k psi but I'm thinking I probably don't want that much recoil. Oh and my rifle is Marlin GBL, I think the barrel is about 18 inches.

So, does the data that runs up to about 28k psi need gas checks?

Oh and one other quick question, the Lee 450gr mold looks like it has a pretty long nose on it. Will it feed through a levergun?

[TMenezes]

As a quick side note, I don't generally size my Lee 340gr slugs as they drop at about .459 so I just tumble lube with 45/45/10 and load them up.

[Crusty Deary Ol'Coot]

TMenezes,

One extremely important factor in your situation is bullet to bore fit.

Then lube quality and alloy.

I think you need to be considering velocity as the pressures will change, along with the pressure curve with the powder in use.

With a good fit, alloy and lube you should be good to go for most velocities below 1400 - 1500fps.

Your rifle will tell you if something is wrong in the equation.

You will have your money well spent if you go to someone like Tom at Accurate Molds, and have him make you a 4 cavity mold for your plus 400gr bullets.

Tom will know what molds will work for the Marlin.

Choose a style with a Wide Flat Nose (WFN) and put it out the tube at 1300 - 1500fps and it will take care of any game your likely to hunt without over kill and excessive meat loss.

My Load is a 465gr (nominal) WFN cast of 50/50 clip on Wheel Weights/lead, which is water quenched as it falls from the mold and shot ahead of 47.5gr of H335 for a velocity of 1650fps.

Sized .460

It is a gas checked bullet.

I have tested and fired a sizable bunch of rounds with a 355gr WFN - gas checked - at velocities as high as 2500fps.

However, the 355gr at 2300fps was major over kill with a huge wound channel.

By the way, the 465gr WFN works fine in a Marlin. I'm shooting a RUGER #1 - 45/70

Crusty Deary Ol'Coot

[TMenezes]

Thanks Crusty, do you think my 45/45/10 Tumble Lube will work or should I look other types of lube for this application?

[Crusty Deary Ol'Coot]

Well, lots of people use and like it, so be that as it may.

I have never bought into tumble lube, having sizers/lubers well before Lee came on the scene.

Don't like the thought or looks of that mess.

Like I said, be that as it may.

So, for that reason, you need to look at your personal results and your feelings on the tumble lube situation.

I have just always sized my bullets, and as said, used the sizer/luber to do so.

I have both RCBS and Lyman.

For my 45/70, I size and lube in two stages as per the recommendations of my 465gr mold maker.

I size the bullets as soon as possible after casting and quenching and do so in a "Lee style" push through die of .460 dia. I may or may not seat the gas check at that point.

Then at some later date, I wait at least 7 days after casting before shooting those bullets, I run them through the sizer/luber with a .461 dia die.

The reason for the two dies is to accomplish the sizing - .460 - ASAP after casting so as to not disturb the aged surface hardness when I lube in the .461 sizer/luber die.

Will follow this thread to see what may be suggested and how you decide to go.

Good luck, and enjoy that 45/70!

Always glad to chat and exchange ideas.

Crusty Deary Ol'Coot

[longbow]

Many years ago I had a Siamese Mauser converted to .45-70 and never had a GC mould. I had 3 moulds ~ 385 gr., 405 gr. and 500 gr. all PB. I loaded right to Hornady manual max. jacketed loads for Siamese Mauser and Ruger #1 with little trouble. Some powders did result in a bit of leading about 4" from the muzzle on out but a 410 fiber wad under the boolit solved that. Later I got a Marlin 1895 and loaded that right to book max. loads for the Marlin again using PB boolits and had no problems at all (no wad required).

As stated, good boolit fit is most important.

Nowadays I would not be loading that hot as the recoil tended to be a bit abusive. In any case, my take is that a gas check is not needed though certainly it wouldn't hurt. If in doubt and you will only be buying one mould the gas check would be good insurance.

Oh, I cast mostly straight wheelweights for those boolits and not quenched or oven heat treated.

Longbow

[Crusty Deary Ol'Coot]

Good info Longbow.

I also use mostly straight WW, but have gone to the 50/50 alloy and quenched at the recommendation or the maker of my 465gr mold.

So far his info has been spot on, so I've just stayed with it.

CDOC

[TMenezes]

Thanks guys, that helps allot. My current Lee mold doesn't have a gas check and I don't thknk the other Lee molds I was thinking about have them but I would have to check to be sure. So far I have never loaded any caliber to max pressures. Usually low powered target loads and a few that were upper mid range for Ruger 45 Colt. I like to keep my reloading simple instead of trying to push the envelope. What extra time and money I have is usually spent on the kids. So whatever Lee molds are available is probably what I will go with.

Anybody know if gas checks are available by the hundred? All I can find is bags of thousand. I would like to get a hundred each in 357, 44, 45 pistol, and 45 rifle. In thousand pack bags that's WAY more than I could ever use as most of my loads don't need them.

[Char-Gar]

The RCBS 405 grain FN bullet was designed for the Marlin levergun and is one of the best for that caliber and rifle. It does not need a gas check.

It is pointless to shoot a 45-70 at any velocity that requires the use of a gas check. A 400 grain 45 caliber bullet going 1,400 fps will shoot through any game animal in North America from any angle. Any extra energy grained from any extra velocity will just be wasted on the terrain behind what ever animal you shoot.

Boost the velocity any higher and you will have ferocious recoil and nothing to show for it. There is no way this round can be turned into a flat shooting rifle and caliber.

I will point out that millions of American Bison/Buffalo were killed by the same type bullet leaving the muzzle of rifles at 1,100 to 1,200 fps.

[303carbine]

I would guess about 1500 fps before a gas check would be needed, a lot would depend on bullet hardness.
I shoot the gas checked 405 RCBS bullet at 1640 fps. out of my 86, very accurate and zero leading.
The benefit of a gas check is so the bullet base doesn't get deformed under fire, this usually causes erratic accuracy and barrel leading.
Bevel base bullets allow gas to get by the bullet which can cause accuracy problems as well.
Some bullet companies make undersized super hard cast bullets with a bevel base, they look good and don't get damaged during shipping, but good looks don't equal accuracy.

[waco]

The RCBS 405 grain FN bullet was designed for the Marlin levergun and is one of the best for that caliber and rifle. It does not need a gas check.

It is pointless to shoot a 45-70 at any velocity that requires the use of a gas check. A 400 grain 45 caliber bullet going 1,400 fps will shoot through any game animal in North America from any angle. Any extra energy grained from any extra velocity will just be wasted on the terrain behind what ever animal you shoot.

Boost the velocity any higher and you will have ferocious recoil and nothing to show for it. There is no way this round can be turned into a flat shooting rifle and caliber.

I will point out that millions of American Bison/Buffalo were killed by the same type bullet leaving the muzzle of rifles at 1,100 to 1,200 fps.

I agree with Charles 100%

You can do 1,500-1,600 with a PB and smoke anything you want. GC's are one more step, and expensive....

[Crusty Deary Ol'Coot]

It is thought by some experienced and published folk, that at times a gas check will improve accuracy.

I have never, at least to this point shot any 45/70 loads with non-gas check bullets.

Most of my .444 or .44 bullets are gas checked.

What ever floats your boat.

Crusty Deary Ol'Coot

[starmac]

Do most longe range target shooters use gas checks??

[aspangler]

A Lee 405 at 1400-1500 fps will kill anything on the North American continent and won't kill your shoulder in the process. 50/50 WW/pure and no GC. Potent medicine in anyones book.

[Whiterabbit]

I have noticed that typically using a gas check will improve group size at ANY velocity. Just as often, that improvement may be splitting hairs (we all have PB loads with small groups), but still it is there.

I view using GC's as a crutch to allow for larger variances in loading practices without impacting performance. If snapping on a gas check means I can control alloy less, control lube less, worry less about sorting casts, use alternative powders that perform poorly on PB bullets, then the 4 cent per bullet cost, along with the installation time cost is justified.

It's not always justified. But sometimes, it is. Even for low pressure, low velocity rounds.

[Crusty Deary Ol'Coot]

Good points Whiterabbit.

You might check out the "Blammer" Checks from DJ's gas checks. Should be able to find the link here on this forum.

I bought a sample 1000 awhile ago. The are slight thicker then the Hornady and go on better/easier.

The time and slight cost involved still makes gas check cast boolit cheap when compared to 30 - 40 dollars per hundred for "J" bullets

Crusty Deary Ol'Coot

[Geezer in NH]

Velocities a Ruger #1 can achieve??? Other recoil will let you know when to fast IMHO

[Crusty Deary Ol'Coot]

I am not nearly to the velocity levels my #1 is safe to handle, and after the results, Waaaaaay Over Kill, I saw on my first cast bullet critter with a 355gr Wide Flat Nose at muzzle velocity of 2300fps, I have not intention of ever going there again.

Being one who seldom loads or shoots other then what I have had good results with and/or what I consider optimum, I could experiment with a non-gas check bullet close to the 1650fps velocity I using with my 465gr WFN, but see little point in messing with success.

Yep, could push for a lot more velocity, but see no need. Or, buy another mold and try plain base boolits, but as said, pleased with the current results.

I did test those 355gr boolits to a bit higher then 2500fps, and if they had shown great groups I might still be hunting with that boolit,

However, after seeing the great results with the 465gr at 1650fps, I'd sure hate to go back to that time bomb.

It didn't explode, but Oh MY what a hole that Wide Flat Nose bullet left at 2300fps.

Crusty Deary Ol'Coot