.45/70 data

444shooter

444shooter

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I have some Hornady 350gr RN and H4198, and checked Hodgdon's online data for lever actions. They suggest a starting load of 48.5grs and go up to 54grs.
Is that a typo?? Because Hornday's manual shows 48grs as max :eek:
 
That is very common with a lot of data sources regardless of cartridge.

Hodgdon data shows just under ~40000 cup as maximum pressure for that load while Hornady doesn't specify the individual pressures for any particular load only that all their lever gun data is all under 40000 cup. It could well be they stopped at around 35000 cup.

I usually start with the average starting loads from several sources and they work up to the desired velocity while watching for pressure signs. The problem with the 45-70 is that the "normal" pressure signs don't show until one is way over maximum pressure levels for most lever action rifles. 2050 fps - 2100 fps out of a 22" barrel with a jacketed 350 grain bullet is a high as I would push a Marlin.
 
You should contact Bob Mitchell at
13 Orchard Drive
RR # 1
Lindsay, ON
K9V 4R1

and ask him to send you his own manual on the 45-70. He probably knows more about the 45-70 than most people on the planet, including the "reloading manual writers". He gives an eye-opening account of his own personal research on the full potential of the 45-70 handloaded round for three guns in particular: the Ruger #1, the 1895 Marlin, and the NEF Handi-Rifle 45-70 single shot.

I won't be going back to my "store bought" manuals for my 45-70 Guide Gun. It's well worth the $20 he asks for it. I don't have a phone number but you can get it from 411 online.
 
444,

EDIT TO ADD: The data I used was Hodgdon LEVER ACTION GUNS, not the MODERN RIFLES which was even hotter

I just got back from testing a few rounds of 54.0 gr H4198 and the 350 gr Hornady bullet out of my Guide Gun.

I am not sure what to think and would be interested to hear opinions.

I got velocities averaging 2199fps (low 2168 to high 2248) out of the 18.5" barrel. The Hodgdon data says 2141 fps out of their test barrel which is undoubtedly longer so I expect I was hot.

The gun functioned fine, extraction was not sticky, recoil was mild and good accuracy (first three rounds were all touching at 50m with open sights).

There was slight flattening of primers but bothered me was a slight but noticable bulge in the brass just back of the outside of the chamber. I know Marlins have generous chambers and looking at the published data I expect this is a high pressure load for a Marlin and definitely for my gun. I expect that I would see the same in any other Marlin but I am new to these guns so of course am a little frustrated and hope I don't have a wimpy gun.

Has anyone else fired these loads? Is this a normal Marlin pressure sign?

I also see that the Hodgdon data is about 4-6 grains hotter than any other source so I would recommend starting much lower and approaching cautiously, I won't be using 54.0 gr, will be staying a fair bit lower.

Cheers
 
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My Hornady book shows 3 different entries for the 45-70. Trapdoor...Marlin 1895 and...45-70 ruger. i see you have the marlin and mine shows a low of 36.7 gr. 4198 and high of 47.1 for this gun.

The only entry showing near that which you noted is for the 300 hollow point bullet.
 
Ike said:
444,

EDIT TO ADD: The data I used was Hodgdon LEVER ACTION GUNS, not the MODERN RIFLES which was even hotter

I just got back from testing a few rounds of 54.0 gr H4198 and the 350 gr Hornady bullet out of my Guide Gun.

I am not sure what to think and would be interested to hear opinions.

I got velocities averaging 2199fps (low 2168 to high 2248) out of the 18.5" barrel. The Hodgdon data says 2141 fps out of their test barrel which is undoubtedly longer so I expect I was hot.



.

Cheers
Click to expand...



The notion of longer barrel= faster is not always the case. In med to fast burners like 4198 the burn can happen fast enough that the longer tube just creates drag and actually slows it slightly. To add barrel length is beneficial for sight radius or in cartridges using med to slow powders in over bore chambers. Your short barrel may actually burp em out a slight bit quicker, but harder to hit with if using open irons. If you level off around 50-51 grains in that gun, you will pick up a couple benefits. It will most likely be more accurate, and your muzzle wont be pointed to the sky forever and a day negating a quick second shot. If you loose 50-100 fps on that projectile I wouldnt sweat it. The 458's are so low in ballistic efficiency that that a few FPS doesnt effect trajectory much anyway

Just for fun pop up this program and enter your numbers given that your BC is around .195 and see the trajectory within the distance you'll be shooting. Then change only the speed by 50 or 70 FPS and watch how little trajectory benefit you've gained for all that hoopla

http://www.sav10ml.com/pages/load_data/traj_basic_dat.html
 
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One of the problems with published .45/70 loads is that they tend to be rifle specific, so data is bound to differ between loading manuals. A quick look in my manuals suggests to me that 48 grs is a maximum load with a jacketed 350 gr bullet in the Marlin and anything above that should be reserved for the the Ruger #1.
 
Hi asusual,
Already thought of that,,,, ;)
You're right about velocity loss, I looked at some test data for IMR 4198 and the gun loses about 40 - 100 fps between the 18 and a 26" barrel depending on load.
A also ran the trajectory before I loaded them and it varies a little bit for a 150m zero but not too much until the bullet is slowed a couple hundred fps.

Recoil and muzzle jump wasn't bad at all, felt less than a shotgun with 3" slug so that wasn't an issue :)

I did decide not to try to turn this gun into a magnum and that the Hodgdon data is a little hotter than I need. 50-ish grains is goodand if I can improve loads from three shots touching I will like that too :)

Thanks for the comments
Cheers
 
A important thing to think about when loading for a Marlin 1895 45-70 rifle is that you maybe pushing the capabilities of the rifle without reaching any pressure signs...

Stay safely within the Lever Action reloading guide lines and you will never have an issue push it and one day your rifle may give up... :(
 
Camp Cook said:
A important thing to think about when loading for a Marlin 1895 45-70 rifle is that you maybe pushing the capabilities of the rifle without reaching any pressure signs...

Stay safely within the Lever Action reloading guide lines and you will never have an issue push it and one day your rifle may give up... :(
Click to expand...

I hear you CC, even though in today's litigous society I would expect the loads are likely fine (much less brass smiling than I used to get out of my Glock chamber) but think that I will class the Hodgdon loads are a little hotter than I will go. (Although they were nothing like the ones you had me shooting out of your gun) ;)

I checked the brass out again and the bulging was minimal
Remember to send me that load data too :)

Cheers
 
Ike said:
444,

EDIT TO ADD: The data I used was Hodgdon LEVER ACTION GUNS, not the MODERN RIFLES which was even hotter

I just got back from testing a few rounds of 54.0 gr H4198 and the 350 gr Hornady bullet out of my Guide Gun.

I am not sure what to think and would be interested to hear opinions.

I got velocities averaging 2199fps (low 2168 to high 2248) out of the 18.5" barrel. The Hodgdon data says 2141 fps out of their test barrel which is undoubtedly longer so I expect I was hot.

The gun functioned fine, extraction was not sticky, recoil was mild and good accuracy (first three rounds were all touching at 50m with open sights).

There was slight flattening of primers but bothered me was a slight but noticable bulge in the brass just back of the outside of the chamber. I know Marlins have generous chambers and looking at the published data I expect this is a high pressure load for a Marlin and definitely for my gun. I expect that I would see the same in any other Marlin but I am new to these guns so of course am a little frustrated and hope I don't have a wimpy gun.

Has anyone else fired these loads? Is this a normal Marlin pressure sign?

I also see that the Hodgdon data is about 4-6 grains hotter than any other source so I would recommend starting much lower and approaching cautiously, I won't be using 54.0 gr, will be staying a fair bit lower.

Cheers
Click to expand...

The slight widening above the rim isn't serious and pretty normal on first firing. Had the same concerns, but subsequent loads seemed to maintain the overall width. The Hodgdon starting load for the 350 RN is close to my hunting load - for now - (56.8 grs IMR3031). Their max load is I think 61.0, a compressed load. In my XLR I'm getting 2200 -2225 fps with the lighter load and recoil is pretty hilarious. Some would call it a heavy push - not me! It's a helluva thump, but the factory pad and the stock on the XLR soak it up pretty well, actually. I think the key with these rifles is to be meticulous about your case prep and inspection, and I hand measure every charge, unless I'm scooping 16.5 or so grs of Blue Dot to push a cheap 300 gr HP at squirrels. I'm pretty well convinced you could get away with dipping the cases into a bucket of powder, dumping out just enough to make room to seat a bullet and not worry - with these slow powders, the excess burns outside the barrel anyway! (not that I'd EVER recommend it). I've wanted to get the 350 RN to 2400 fps, but I'm rethinking that strategy. With the 56.8 gr load @ 2200+, you're generating something like 3800 ft/lbs at the muzzle. With a .458 diameter bullet that's gonna expand, small wonder the old Gov't can and does flatten anything on this continent......they sure are a hoot.
 
I use 54gr H322 with my 350gr Hornady bullets.

Sorry Ike I have to dig out my data will pm it to you as soon as I get to it.

I have used almost every powder that works in the 45-70 I now use H322 exclusily it is not tempture sensative like many of the other powders, burns super clean and also gives great velocities in the GG's shorter barrel.
 
I'm with "dorm"...Mitchell is the man for info on hot 45/70 loads, he prefers heavier bullets in the 45/70 as they can penetrate deep as well as expand. He gets 465gr. cast bullets up to 2000fps in the Marlin and slightly less in the NEF. He uses a Ruger #1 to get .458 type velocities.
 
asusual said:
Then I dont even want to read his works. If he's one of these "magnum the 45/70 "guys, I class him a doof
Click to expand...

Not me...

Anyone that can safely work with loads for specific cartridges in rifles that can safely handle the pressures that those loads generate is definately not a doof...
 
Hope I am not hijacking the original thread but here is the first group I fired with the 54.0 gr H4198, open sights at 50m. Not stellar I know but not a bad start, I will have to scope it just to work up a load.
I am going to try some loads at 51.0 or 52.0 grains to see where the brass starts to expand noticeably and chrony them as well. I tried a round at 50.0 and it was fine in my gun.
Cheers
45-70350gr54grH4198.jpg
 
i don't want to hijack the thread here either,but B. Mitchell is one very, savy, experienced experimenter. His loads were pressure tested by Accurate Arms and found safe, his book is a joy to read. I think that he and others have just brought the 45/70 up to date, for those that want that.
 
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