45-70 SUBS - 405gr LFP/Titegroup

[mobo215]

Hodgdon RLDC has a subsonic load listed for 45-70:

13.0gr Titegroup
410 HDY SUB-X
COAL: 2.547"
MV: 1005 FPS
27,900 PSI

I don't have the 410gr bullets, so I tried a small batch of ACME 405 LFP over 13.0gr Titegroup. I seated them a bit deeper to crimp to the cannelure. Velocities verified with a Garmin Xero C1:

Henry X 45-70, 20 shots:

• AVG Kinetic Energy: 1242.3 FT-LBS
• AVG MV: 1175.5 FPS
• EX SPREAD: 18.0 FPS
• STD DEV: 4.8 FPS
• MIN VEL: 1165.6
• MAX VEL: 1183.6

First, these SD and XS numbers are pretty good! Unfortunately, these were supersonic and three of the 20 shots hit the paper sideways. Even if they came in under the sonic barrier, I wouldn't want a baffle strike on my Obsidian 45. I'm wondering if I can trust any subsonic load that uses this 405gr LFP bullet to stabilize. I'd like to work up a load to launch 300gr Hornady Interlocks at subsonic velocities, using Titegroup. I can't find any data that even puts me in the ballpark, but I'm guessing 8 or 9 grains of Titegroup will get close.

Anybody try something like this? I'm looking for the lowest velocity possible that will stabilize reliably.

 

[hlee]

Start here for stability estimates…

Twist Rate Stability Calculator

Our newly updated Twist Rate Stability Calculator not only tells you what your SG is, but it also lets you know if you are reaching your optimized BC.

bergerbullets.com

Or here

Bullet Gyroscopic Stability Calculator

Calculate the Gyroscopic stability of a bullet with the Miller approximation.

bisonballistics.com

Or, put “ballistic stability calculator” into your search engine of choice.

 

[mobo215]

Start here for stability estimates…

Twist Rate Stability Calculator

Our newly updated Twist Rate Stability Calculator not only tells you what your SG is, but it also lets you know if you are reaching your optimized BC.

bergerbullets.com

Or here

Bullet Gyroscopic Stability Calculator

Calculate the Gyroscopic stability of a bullet with the Miller approximation.

bisonballistics.com

Or, put “ballistic stability calculator” into your search engine of choice.

The Berger site only goes up to .375, so I'm using the other site. Something doesn't compute. The 405 LFP I was using would be *over-stabilized*, even down to 850 FPS:

What am I missing here? Why did I get 3 keyhole shots?

 

[hlee]

The Berger site only goes up to .375, so I'm using the other site. Something doesn't compute. The 405 LFP I was using would be *over-stabilized*, even down to 850 FPS:

View attachment 8492104

What am I missing here? Why did I get 3 keyhole shots?

I’m not 100% confident in the Bison ballistics as it seems to be calculating Sg from supersonic velocities and extrapolating to subsonic.

It may be informative to put some reasonable values into the Berger calculator, and then check the Bison calculator against that.

 

[hlee]

That said, I was keyholing 22 cal bullets from a 6.5 twist 22 arc barrel, once the velocity got “too high” in my test ladder.

 

[mobo215]

I’m not 100% confident in the Bison ballistics as it seems to be calculating Sg from supersonic velocities and extrapolating to subsonic.

It may be informative to put some reasonable values into the Berger calculator, and then check the Bison calculator against that.

I did notice that despite entering 850fps as the velocity, the chart starts at 2000fps. Not sure what to make of that.

 

[redbullitt]

For subsonic 4570 the best thing you can do is load a big bullet if your rifle can do it, a 600ish grain postel etc gives me the best luck. 4570 is a big case... too big for good subs really. The best fix ive found is making your own big cast bullets to eat up the case space. Also can get rifle set up for cut down 4570 cases... lol but that's a rabbit hole.

If the acme cast bullets are not playing nice with your barrel they can do all kinds of crazy things on their way to target. Keyholes can happen very easily.

Commercial cast bullets tend to be of very hard alloys that play havok on some types of rifling, they may not obturate to the barrel well in low pressure loads, and often they simply are not fat enough. Excess pressure for the bullet base can easily make keyholes too. Even the bullet lube they used may not do well at low velocities or vice versa.

All this can easily cause barrel leading and distort the bullet to make it do crazy things in flight you don't normally see in jacketed bullets.

Another thing to consider... your cases may need cast bullet prep! Generally brass sized for jacket bullets will swage cast bullets down too small for your barrel, resulting in poor shooting ammo. Good cast bullets in 4570 are often .459 or bigger depending on what your rifle can chamber. Thiccc is good if it can chamber. Noe and Lyman make great tools to prep your cases for cast bullets to work well.

For powders... Trail boss tin star and unique have been the easiest to work with here, though very hard to find lately. Titegroup may be a little fast/harsh for a plain base cast bullet, causing your keyholes.

I'm not sure what your twist is, but my Marlin shoots slow 405 cast bullets very well. I'd be surprised if yours wont since that is sorta THE 4570 bullet.

 

[redbullitt]

For subsonic 4570 the best thing you can do is load a big bullet if your rifle can do it, a 600ish grain postel etc gives me the best luck. 4570 is a big case... too big for good subs really. The best fix ive found is making your own big cast bullets to eat up the case space. Also can get rifle set up for cut down 4570 cases... lol but that's a rabbit hole.

If the acme cast bullets are not playing nice with your barrel they can do all kinds of crazy things on their way to target. Keyholes can happen very easily.

Commercial cast bullets tend to be of very hard alloys that play havok on some types of rifling, they may not obturate to the barrel well in low pressure loads, and often they simply are not fat enough. Excess pressure for the bullet base can easily make keyholes too. Even the bullet lube they used may not do well at low velocities or vice versa.

All this can easily cause barrel leading and distort the bullet to make it do crazy things in flight you don't normally see in jacketed bullets.

Another thing to consider... your cases may need cast bullet prep! Generally brass sized for jacket bullets will swage cast bullets down too small for your barrel, resulting in poor shooting ammo. Good cast bullets in 4570 are often .459 or bigger depending on what your rifle can chamber. Thiccc is good if it can chamber. Noe and Lyman make great tools to prep your cases for cast bullets to work well.

For powders... Trail boss tin star and unique have been the easiest to work with here, though very hard to find lately. Titegroup may be a little fast/harsh for a plain base cast bullet, causing your keyholes.

I'm not sure what your twist is, but my Marlin shoots slow 405 cast bullet very well. I'd be surprised if yours wont since that is sorta THE 4570 bullet. Also you are not shooting them very slow to where I'd think twist will be an issue unless henry really messed up on specs for that barrel.

Also worth mentioning that, unless I missed it, you'll want to use coated cast bullets in the suppressor. They make a mess in there otherwise, and a huge pain if the can cannot be taken apart.

 

[wvfarrier]

I had the best results with 500+ grain projectiles for sub loads. At one point I was loading 600 grain hard cast lead (i forget which NOE mold) at 950fps. They were absolute murder on deer. Sounded like a sledge hammer hitting a side of beef. Basically like shooting them with a 12g slug.

 

[mobo215]

For subsonic 4570 the best thing you can do is load a big bullet if your rifle can do it, a 600ish grain postel etc gives me the best luck. 4570 is a big case... too big for good subs really. The best fix ive found is making your own big cast bullets to eat up the case space. Also can get rifle set up for cut down 4570 cases... lol but that's a rabbit hole.

If the acme cast bullets are not playing nice with your barrel they can do all kinds of crazy things on their way to target. Keyholes can happen very easily.

Commercial cast bullets tend to be of very hard alloys that play havok on some types of rifling, they may not obturate to the barrel well in low pressure loads, and often they simply are not fat enough. Excess pressure for the bullet base can easily make keyholes too. Even the bullet lube they used may not do well at low velocities or vice versa.

All this can easily cause barrel leading and distort the bullet to make it do crazy things in flight you don't normally see in jacketed bullets.

Another thing to consider... your cases may need cast bullet prep! Generally brass sized for jacket bullets will swage cast bullets down too small for your barrel, resulting in poor shooting ammo. Good cast bullets in 4570 are often .459 or bigger depending on what your rifle can chamber. Thiccc is good if it can chamber. Noe and Lyman make great tools to prep your cases for cast bullets to work well.

For powders... Trail boss tin star and unique have been the easiest to work with here, though very hard to find lately. Titegroup may be a little fast/harsh for a plain base cast bullet, causing your keyholes.

I'm not sure what your twist is, but my Marlin shoots slow 405 cast bullet very well. I'd be surprised if yours wont since that is sorta THE 4570 bullet. Also you are not shooting them very slow to where I'd think twist will be an issue unless henry really messed up on specs for that barrel.

Also worth mentioning that, unless I missed it, you'll want to use coated cast bullets in the suppressor. They make a mess in there otherwise, and a huge pain if the can cannot be taken apart.

The ACME 405 LFP's I'm using are coated. I measured a few of them and the diameter is exactly .458". I was expecting them to be .459", but they were not.

I think you may be on to something. I was using load data for the 410gr SUB-X bullet, which is jacketed. The listed velocity was 1005fps with 13.0gr of Titegroup. I think that the lead bullet was almost 200fps faster because it's 0.001" smaller in diameter than is typical for lead bullets, and because lead swages into the rifling with less pressure than jacketed bullets do.

17 out of 20 shots made perfectly clean holes in the target, while 3 keyholed. You're probably right that something is deforming the bullet base. On the other hand, since velocities were very consistent, I can only assume pressures are consistent as well. Titegroup really does a nice job keeping velocities in a tight band in the large cases.

410gr SUB-X bullets are over $1/bullet. I'd really like that make this work with less expensive lead bullets in that weight class or cheaper jacketed bullets in the neighborhood of 300gr, such as the Hornady Interlock HP.

 

[redbullitt]

Cast usually goes a good bit faster in same loading since it moves through the barrel much easier vs copper jacketed.

You should be able to get cast 405 or heavier, if not those to shoot. Those bullets at .458 are smaller diameter than I've shot in any of mine successfully and that's definitely the direction id be looking first.

Any leading in bore?

Perhaps try another cast bullet. Some places will let you pick diameter. Generally need to be .001 or .002 over bore at least. Bigger is good too if throat allows it and you can keep your brass from swaging them down.

Cast is the best way to shoot 4570 unless you've got deep pockets lol. Just takes a little experimenting to get it right, especially when using less ideal commercial cast.

 

[mobo215]

UPDATE:
I had a box (20rds) of 405gr coated ACME LFP and loaded them with 8.6gr of Titegroup. Through my Henry Big Boy X 19.x" barrel:

Avg: 924.4 fps
XS: 47.8 fps
SD: 11.4 fps
Max: 946.4
Min: 898.6
KE (ft-lbs): ~775

All 20 shots punched perfectly sharp holes in paper at 100 yds - looked just like a paper punch was used. Recoil was nice and soft, and since the big 'ol fiber optic sight covers almost the entire target at 100 yds, I was happy to see them grouped mostly inside of an 8" circle. I could try bumping the powder charge up a bit to get closer to 1050 fps, but I'm pretty happy with this load as it is.

I think I'm going to put a 1-6x LPVO scope on this rifle and figure out the hold-over/come-up for 200yds. Lots of fun lobbing these big 405gr artillery shells at 200+ yds. Maybe I'll get them out to 300+ yds someday.

I have no idea where I got this load data from, but I need to get better at writing things down before I blow my face off!

 

[sirhrmechanic]

Loading for pumpkin slingers is a whole different art versus loading modern bottleneck high-pressure cartridges.

Bullet weight as well as length play into it. I doubt any of the modern ballistic calculators really do 45/70 right.

If you check over in the Vintage area, there’s been a bunch of stuff over the years about loading for big bore slow, moving cartridges in sharps and even some of the heavy muzzle loaders.

Cheers!

 

[mobo215]

Loading for pumpkin slingers is a whole different art versus loading modern bottleneck high-pressure cartridges.

Bullet weight as well as length play into it. I doubt any of the modern ballistic calculators really do 45/70 right.

If you check over in the Vintage area, there’s been a bunch of stuff over the years about loading for big bore slow, moving cartridges in sharps and even some of the heavy muzzle loaders.

Cheers!

Pumpkin-chunkin appeals to me because I'm in Philly, where I would have to drive 4+ hours to have access to a range with 600-1000 yards. Most ranges near me are 100 yds max, with the occasional 200 yd range if you happen to know somebody who is a member and can take you there as a guest. I am a member at Mifflin County Sportsmens, but I haven't had the chance to drive out there because I work a LOT and that's an overnight journey from Philly.

Almost every range I've tried to join near Philly is full and not taking any new members. So I shoot "minute-of-2L-soda-bottle" at 100-200 yards with subsonic mortars and open sights and it's lots of fun. I have a Ruger American .300 Blackout, Henry 45-70, Henry .38spl/.357 mag, and a 16" Remington 700 for such things.

One of these days I'll get to stretch out my Bergara 6.5 CM to 600+ yds. I think my 16" .308 could probably stretch out to 600 as well.

 

[st1650]

If you're shooting these big subs, find some tinstar or trailboss or get some 600+gr cast and use AA1680

 

[45-90]

L to R 510 Whisper with 750 gr,
45 Colt 500 gr, ... 450 Bushmaster 16 twist barrel 500 gr...
And 45-70 500 gr cast 13 gr Unique 975 fps.

 

[Atomic_Lobster]

I had issues with my Buffalo Classic 45-70 shooting 500gr boolits casted at .457 and they would keyhole at 100 yards
So I started paper patching my boolits to .460 and the keyholes went away
Now I'm using BP and got to test my homemade redneck boolit mold to see how they shoot
They weight 389gr
They are hand seated in some old beat up chrome plated brass
Just got 50 new brass pieces this week so I'll start using those it these two shoot good

 

[45-90]

Cast bullets in 45-70 should be .459" for general best accuracy.
Even light bullets in 300 gr area if under very much will keyhole at 30 yds.
I tried some 300 gr .452" bullets to find out, even with high velocity, high pressure loads and heavy crimp they would not obturate to fill the bore, as some have claimed...only keyhole.

 

[mobo215]

Cast bullets in 45-70 should be .459" for general best accuracy.
Even light bullets in 300 gr area if under very much will keyhole at 30 yds.
I tried some 300 gr .452" bullets to find out, even with high velocity, high pressure loads and heavy crimp they would not obturate to fill the bore, as some have claimed...only keyhole.

ACME's website actually advertises these as 0.458" in RED and 0.459" in BLACK:

https://acmebullet.com/product-category/bullets/?page=1&cs=45_70&bs=no-brand

So... I'll shoot the red ones and then buy black from now on. Pressure will increase, but I'm sure it won't blow my face off if I stick with 8.6gr of Titegroup.

 

[45-90]

ACME's website actually advertises these as 0.458" in RED and 0.459" in BLACK:

https://acmebullet.com/product-category/bullets/?page=1&cs=45_70&bs=no-brand

So... I'll shoot the red ones and then buy black from now on. Pressure will increase, but I'm sure it won't blow my face off if I stick with 8.6gr of Titegroup.

Because so many old rifles had the bore size vary, you were supposed to slug your individual barrel and "mike" the slug and order your bullets or bullet mold .001" to 002" oversize, and size down in your lubrication/sizing press to .001" over your bore diameter.
Read some old Lyman cast bullet manuals.

Pressure increase is minimal between the two bullets going down the .458 bore, between .458" and .459" lead bullets.
Use whatever powder works for you, and report back so others can give it a try.

 

[redbullitt]

Definitely watch out for skinny cast bullets. Cleaning lead out of a rifle barrel is annoying....

When I cast mine, I try and see how fat I can use and still get them to chamber with my brass. MOST all of my 4570 stuff takes a .460 bullet no trouble at all in any brass I have on hand. Running them fatter seems to help with accuracy and preventing leading.

Some of my older rifles need a fatter bullet for sure, but can tolerate a .459 or .460. Only way to know for sure is to check it in yours. Rifle will tell ya pretty quick.

Also be aware, when shooting slow stuff, commercial cast tends to be hard alloys, and often a hard high velocity lube. Low velocity lube and softer bullets can help a lot if your rifle is being stubborn. May not be a problem, but something to look at if issues pop up.

 

[SpeedyR]

I've been working on some 340gr (Lee 457-340-F) and 490gr (Lyman 457406) cast powder coated rounds. My two powders I've been playing with are VV 3N37 and IMR 4227. So far I've had good results with the following:

340gr w/ 19.0gr 4227 ~975fps (garmin Xero)
w/ 12.5gr 3N37 ~965fps
490gr w/ 19.0gr 4227 ~865-870fps
w/ 13.0gr 3N37 ~927fps

I have a 405 mold as well (Lyman 457193) and had planned to try around 20gr 4227 and maybe 10gr N320, both should be around 975fps.

Both of these are great in my Marlin Dark 45-70 (ruger manufactured). Hopefully will get them to the range in the next few weeks to test the accuracy but at my local indoor range, no key holing and decent accuracy just playing around.

 

[45-90]

Hodgdon RLDC has a subsonic load listed for 45-70:

13.0gr Titegroup
410 HDY SUB-X
COAL: 2.547"
MV: 1005 FPS
27,900 PSI

I don't have the 410gr bullets, so I tried a small batch of ACME 405 LFP over 13.0gr Titegroup. I seated them a bit deeper to crimp to the cannelure. Velocities verified with a Garmin Xero C1:

Henry X 45-70, 20 shots:

• AVG Kinetic Energy: 1242.3 FT-LBS
• AVG MV: 1175.5 FPS
• EX SPREAD: 18.0 FPS
• STD DEV: 4.8 FPS
• MIN VEL: 1165.6
• MAX VEL: 1183.6

First, these SD and XS numbers are pretty good! Unfortunately, these were supersonic and three of the 20 shots hit the paper sideways. Even if they came in under the sonic barrier, I wouldn't want a baffle strike on my Obsidian 45. I'm wondering if I can trust any subsonic load that uses this 405gr LFP bullet to stabilize. I'd like to work up a load to launch 300gr Hornady Interlocks at subsonic velocities, using Titegroup. I can't find any data that even puts me in the ballpark, but I'm guessing 8 or 9 grains of Titegroup will get close.

Anybody try something like this? I'm looking for the lowest velocity possible that will stabilize reliably.

According to QL, 10 gr of titegroup is lowest for a jacketed 300 gr bullet...anything below that the start pressure is too high.
Go to lead bullets if you want the lowest velocity possible the start pressure is much less here, 4 grains of titegroup is the bottom. Going that low make sure the bullet exits the barrel before loading another bullet behind the one stuck in the barrel.

You should experiment without the suppressor, until you are sure.
Lead bullets can be real soft, smearing lead down the bore, causing bullets not to spin correctly, tearing the bullet surface instead of engaging the rifling or just too much lead build up in your barrel, for the bullet to get a grip.
Hard cast for general plinking, softer lead for hunting where few shots will be fired.

 

[Potsy]

I don’t have a suppressor on my #1, but have still kicked around the idea of subs, as they’re still quieter than supers.

But one thing I’ve noticed is that Titegroup and even Trailboss data seems to kick pressure up towards 30kpsi. Not a problem, but thinking that without a can, that would be louder than something under 20kpsi. I SUSPECT that this is where Unique would shine.

My 16” .45 Colt is noticably quieter with 7.5grn Unique at 1050fps (around 15kpsi) than 9.0grn H-Universal at 1185fps (20kpsi), 270-SAA, unsuppressed. It’s obviously sub vs. super, but still…..