Hornady .45 Gas Check for 45-70?

Reed

Reed

Active Member
I've never given gas check dimensions much thought. Just bought them, used them, and was happy. That was for .30 caliber.

I have my eye on a 405 gr mold over at Mountain Molds for my recently acquired 45-70. Turns out it's Ballard rifling, at .457. I've read that Hornady .45 gas checks are good from .452-.458. Anyone know the actual dimensions of Hornady's .45 gas check inside and out? I'll be sizing at .459. Does anyone have experience sizing the Hornadys at .459? Did they stay tight? Should I care? I read one of Dan's posts on his forum that by the time they launch and obturate, they will be tight.

Sages says Gator checks are .068 in diameter, made for a .426 shank. Anyone happy with those?

Part of Dan's description says:
cut for Hornady 45 check
(can cut for BSS 458 on request)
I did some looking around, but didn't find what BSS 458 refers to. What does it mean?
 
Brad

Brad

Benevolent Overlord and site owner
Staff member
The Hornady checks will be fine. I have used them to size at .460 and had no problems.

How fast are you planning to go? A 45-70 kept under 1500 FPS won’t need a check in my opinion. I have even gone into the 1650 FPS realm with no check and no problems.
 
fiver

fiver

Well-Known Member
I didn't even know Hornady made 45 cal. gas checks.
however my money is on Dan, if he says they fit and that the base obdurates I will believe him.
 
Matt

Matt

Active Member
Don’t know what BSS 458 is, but Hornady .45 caliber gas checks do fit both .452” “handgun” bullets and .458” “rifle” bullets. The Hornady gas checks work very well on my RCBS 458 FP 500 grain bullets.
 
Reed

Reed

Active Member
I don't see going faster than 1600, and even slower if I decide later to try out that 520 gr. Is a 7 lb Marlin going to make me cry "Uncle" with a 405 gr at 1600 with a Limbsaver pad?
 
waco

waco

Springfield, Oregon
I think my 405 load goes around 1400. Plenty for me or anything I’m pointing it at.
 
Reed

Reed

Active Member
Have you done any penetration testing with that 405 @ 1400? Maybe a grizzly's shoulder? Would be interested in hearing anyone's results.
 
CZ93X62

CZ93X62

Official forum enigma
Hornady 45 caliber checks fit and stay when sized to .461". I anneal them in a pot of alloy if I plan to size them to .454" for my Ruger 45 Colt (Lyman #454490, usually); they aren't as recalcitrant to size down if annealed. ALL of my gas-checking gets done in two steps, using the Lyman gas check seater critter to halt the "I" pin's downward travel.

My Mountain Molds 9.3mm mould uses 375" checks, and get sized to .367". Annealing helps here too. Hornady checks give you quite a bit of latitude in the larger diameters if you are willing to "Finish building them", either with annealing and/or flaring.
 
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Brad

Brad

Benevolent Overlord and site owner
Staff member
I have perforated a pair of black bears with a 420 gr plain base at 1650 fps.
Neither bear appreciated it.
True recoil begins around 1700 fps with a 400-420 gr bullet. A 405 Rem jacketed at 2K is invigorating.
 
Reed

Reed

Active Member
Have decided to go with a 420 gr from Mountain Molds, and take Brad's advice about no gas check. I'll be looking for 1400-1550 fps. This is new territory for me, designing the bullet I want. What do I want? I think, pretty much what you see here. I wouldn't mind some critical eyes having a look and offering feedback/suggestions if there is some glaring bone-headed detail. Bore is .451 x .4571. Cerrosafe is on the way to get a picture of the chamber. Playing with it a little in the meantime. Nose length will make loaded round max Marlin length with cases trimmed to 2.090. Is it a good/bad idea to have a slightly smaller front driving band, or is that a Ford/Chevy question?
1597440645693.png 1597440818983.png
 
Bliksem

Bliksem

Active Member
Reed said:
I don't see going faster than 1600, and even slower if I decide later to try out that 520 gr. Is a 7 lb Marlin going to make me cry "Uncle" with a 405 gr at 1600 with a Limbsaver pad?
Click to expand...

One of the few Marlins that I have sold was a 45-70 as it was never a pleasure to shoot no matter the load. I tried, I really tried but even though the 444 Marlin is a handful the 45-70 was not a keeper.

/thread drift warning/

Eventually I traded a cheap AR15 for an older Ruger M77 tang safety in 458WM and now it is my goto hunting rifle. Lee 450gn PB powder coated & sized .459" on top of 33gn SR4759 produces 1~11/2" at 100 yards consistently. In this 9+LBS rifle it is possible to have an enjoyable range session as well as a very good hunting tool. None of the white tail deer, Nilgai or hogs have complained that I was under gunned. ;-))
 
Brad

Brad

Benevolent Overlord and site owner
Staff member
24 gr of 2400

The front band on that would be fine. I prefer nose that has a smooth transition to full diameter.
The bullet Waco mentioned is very good.
 
fiver

fiver

Well-Known Member
I'd take the diameter of that front drive band down too.
the 45-70 doesn't have any throat.
 
CZ93X62

CZ93X62

Official forum enigma
What Fiver said. .050" band length, or shorter. Most 45/70 Marlin throats are non-existent, and contoured like a city street curb edge.
 
RBHarter

RBHarter

West Central AR
I recently shot some 250s , Rapine 458201 . I broke 2000 fps in an 1895G and I will concur that there's no need for that sort of abuse to ones person . PPU factory 405s are quite comfortable to shoot by comparison . I haven't yet clocked those that I recall . I know the Lyman books say you can reach 1200 on Unique and be in Trapdoor levels or burn a lot of real rifle powder for 14-1600 fps and still be in Trapdoor levels with the 405 . I've chosen to go to a 500 and stay subsonic . The 45-500 FN actually will outrun those hotrod 250 and 325 Hornady wonder loads in the long game , either way past 200 yd you have to master ranging and hold over .
 
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