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Discussion Starter #1
Where I hunt in Michigan I can legally use my 45/70 but only if I trim the brass shorter- to no longer than 1.8".

I have done this and have so far shot 4 Whitetail does with my short cased 45/70. I have been using the Hornady 325 grain FTX loaded to an overall cartridge length of about 2.56" and am using a custom Lee Factory Crimp Die to crimp the bullet to that length. As such I am not really hindered by needing to use a shorter case since my powder capacity has not been affected. I am however considering switching to using a Hard Cast lead bullet. Perhaps the 350 grain WLNGC bullet from Beartooth. I have some of those in stock. I think though that I would need to crimp that bullet in the crimp groove, thereby giving me a shorter overall length and reduced case capacity? Am I wrong? Could I use my Lee Factory Crimp Die to crimp a cast lead bullet to whatever overall length I want (within reason)?

The reason I am thinking about switching to a hard cast bullet is so that I can break a shoulder to reduce the chance of losing a deer. The Hornady FTX bullet is killing them just fine but they run off and they do not start bleeding immediately so I do fear one day losing a deer. I suspect that if I can break a shoulder while also penetrating the vitals the deer would more likely drop sooner and with the cast bullet I would not lose much shoulder meat.

So if I do switch to using a hard cast lead bullet and seat that bullet to the crimp groove how would l go about choosing a powder and charge range? I am currently using 48 grains of H4198 and a CCI 200 primer. Muzzle Velocity is right at 1900 fps from my Marlin 1895 SBL.

I have a Leupold 2-7x scope that has extra dots for longer distance aiming points. Zeroed at 100 yards the next dot is on at 150 yards and the next dot is on at 200 yards. Where I hunt my shots have so far been at 55 yards and under from the tree stand but there is an open field on the property that deer hang out in at times and shots could reach 200 yards so it has been nice with my current setup in case such an opportunity were to present itself.

I remember that gun writer John Barsness came up with some formulas on the impact of case capacity with respect to velocity but I do not remember the details. I think it was something like if case capacity is for example 10% less then velocity would be expected to be about 2.5% less. Is that correct? my case at 1.795" is 85% the case capacity of the full length 45/70 case which is 2.105" so if I remember that formula correctly I think I could expect a velocity of about 96% what I would get with a full length case.

If that is right would I just start with a reduced charge of H4198 and work up to no faster than 96% of the velocity that could be had with a full length case? I know that one can typically get a hard cast bullet to safely go faster than a copper jacketed bullet (that is at the same pressure a hard cast bullet will normally be going faster than a jacketed bullet of the same weight and seating depth).

As such I could possibly get the 350 grain hard cast bullet to go 1800 fps in the shorter case without unsafe pressures.

Anyway I would appreciate some input from folks who have either done this loading in a shortened 45/70 case or can advise me on some of these formulas. I have no desire to ruin my gun or myself and have been handloading for 40+ years safely.
 

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Just thinking....it's the case length that needs to be short, or is there a limit on OAL?

With the right lead bullet, could have both the short case and (seated/crimped out) the same internal volume as a 45/70.
 

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So if seated so that the base was at the same depth....then the case would have the same volume. Might end up with an exposed lube groove,but mostly they carry more than enough modern lube for it not to matter if it were filled or not.
 

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The Hornady FTX bullets require a shorter case because if you don't and use the crimp groove they won't feed through a lever gun, the pointed bullet makes them too long. Some states also have restrictions on case length that has something to do with the power level. Either way, you have to put a good crimp on .45-70 rounds if they're used in a tubular magazine. So, if that lead bullet encroaches on powder space when crimped properly, that's the way it has to be. Not something I'd be worried about. Any .45-70 load is going to be more than enough to take down a whitetail. I'd worry more about shot placement and less about how long the case is.
 

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The case of 2.105” has been shortened to 1.795“. How does that affect pressure?
 

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Discussion Starter #7
Pete, if one loads the same amount of powder in a smaller case the pressure will be higher (assuming that the bullet is seated to the same relationship). Is that not clear to you?

With my current load the shorter case is not creating higher pressure since I have the bullet seated out long like it would be if the case were still at 2.105".
 

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Pete, if one loads the same amount of powder in a smaller case the pressure will be higher (assuming that the bullet is seated to the same relationship). Is that not clear to you?

With my current load the shorter case is not creating higher pressure since I have the bullet seated out long like it would be if the case were still at 2.105".
Brian: Please excuse my clumsy question. Yes, the idea is very clear. I experimented with shortened 45-70 cases some years ago. As i had no way to determine the pressure created in the shortened case, i gave the project up. I was hoping that you would have been able to measure the actual pressure.
You have no pressure change.since you have maintained the same interior volume.by sesting the bullet out. Yes? My cases were shortened to 1.5 inches so i could not do what you have done.
 

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If you want to measure the effect of seating a bullet deeper, you'll have to purchase pressure equipment, or find someone who has it.

If you want estimate the % change that small increments in seating deeper will make, you can use something like Quickload. It will be an estimate, but for small changes from a known load, it will give a ballpark idea.

I'd just shorten an Lee FCD and load to the same OAL as before. By far the simplest thing.
 

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Brian: Please excuse my clumsy question. Yes, the idea is very clear. I experimented with shortened 45-70 cases some years ago. As i had no way to determine the pressure created in the shortened case, i gave the project up. I was hoping that you would have been able to measure the actual pressure.
You have no pressure change.since you have maintained the same interior volume.by sesting the bullet out. Yes? My cases were shortened to 1.5 inches so i could not do what you have done.
I'm having some difficulty discerning why you would shorten the case that much. To what purpose? I can understand shortening it to accommodate use of the FTX bullet since normal length when seated exceeds the allowable COAL for use in lever guns. But shorter than that I don't get it.
 

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Discussion Starter #11
MikeG, I did get a custom Lee Factory Crimp Die and am using that with my shortened cases but I do want to try using the Beartooth 350 grain cast bullet and suspect that I will need to seat it such that I can crimp it in the crimp groove. As such it will not still be loaded long like my load using the 325 Hornady FTX so pressure would be higher. Just wondering where to start and likely finish on powder charges.
 

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Discussion Starter #12
Rifter, as I stated in my initial post I need to cut the brass short in order to legally use it where I hunt in Michigan.
 

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Just crimp it wherever. Cast bullets don't mind that too much, and the FCD can easily handle that, crimp groove or no. If it bugs you, you could clean the lube out of the groove that is closest to getting the OAL that you want.
 

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I did the exact same thing with a .35 Rem to hunt in Indiana. I trimmed the cases down to 1.8" and seated a Hornady FTX to the standard depth. I used a modified LFCD to crimp at the location of the trimmed case mouth. This way, case volume was the same. The only change was the length of the brass gripping the sides of the bullet. Works good. I shot two deer with these bullets - both high shoulder shots and both deer crumpled without taking another step.

I also considered changing to a cast bullet and keeping the seating depth the same to keep case volume unchanged (as compared to an untrimmed case). But that would leave lube grooves exposed which I really didn't want to do. Also, the modified LFCD may cause the bullet to move when you go to apply the crimp. If the case mouth is near the edge of one of the lube grooves, when the die goes to squeeze the case mouth, it may push the bullet up or down so the crimp goes into the groove instead of pressing into the circumference of the bullet. You'd just have to watch out for that and see how everything lines up on the particular bullet being used.

By seating a cast bullet deeper into the case, you are not only changing the case volume but also changing the distance from the bullet to the rifling. I'm not certain what effect that would have but I suspect it might have some negative impact on accuracy.

In the end, I just decided to stick with the jacketed bullets when I needed to use the shortened cases to stay within the law.

I'm sorry I can't tell you how much pressures or velocity change when you change case capacity. That's an important consideration I'm sure. But there are other factors to consider as well. I'd be a little afraid to mess around with it.

Are you sure there isn't another jacketed bullet you can seat to normal depth that will break a shoulder effectively? They probably wouldn't be as aerodynamic as the FTX, but your hard cast bullets aren't going to fly like the FTX either. I guess I appreciate your interest in shooting a hard cast bullet with the shortened cases. But, I'm just not sure that it's the most direct way to breaking shoulders while using a shortened case. Of course, if you just like to tinker - have fun and be careful!
 

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Discussion Starter #15
MikeG, thanks for that. I will give it a try loaded longer than the crimp groove would give.

Kart, good info as well. I just do not want to ruin a bunch of meat while breaking the shoulder. Maybe I can find a jacketed bullet that would act like a cast bullet? Any ideas?
 

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Worst case...with a repeater...if the un-crimped round telescopes in....use a smaller expander for a tighter fit.

All I "know" first hand is from 45-70's shortened to 1.95" to run right in a Rolling block Dane (11.7X51r ). Not nearly the pressure you are using (although smokeless...kept to the "trap door loads". Not as much case shortening, but I still made changes for volume when short-seating.....and as a single shot, when long seated (to the same internal volume) used the same basic powder charges as the longer 45/70.

WISH there were some simple conversion I could trust between case volume/loading density/powder type/pressure....just seems to be too many exceptions to the rules to recommend one.
 

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I did not read all posts and someone may have commented.

Some powders do NOT safely allow much charge reduction. s 4198 one of those?? I do know H4895 (only) allws to be reduced to 70% of any PUBLISHED load and they be safe. Check Hodgdons site "YOUTH LOADS" for details, not my opinion. Grandaughter shot a elk twice at nearly 200 yurds w/ 300 WSM and a reduced load.
 

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Langenc,

It's the loading density that can't get too low. Usually, for rifle powders, it's about 70% case fill that is a recommended minimum, but 60% is really still pretty safe. Fast handgun powders are not nearly so sensitive, and lower densities are still safe with most of them.


Brian Carlson,

In your particular situation, since Beartooth's database seems to be having problems, if you could give the length of that bullet and the distance from the nose to the crimp groove, we can probably estimate the charge for you in QuickLOAD or GRT. Or, you could download GRT yourself and try it. I never believe the exact output of the interior ballistics software, but the ratios seem to come out very darn close and you could work it out that way.
 

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Discussion Starter #19
Unclenick, the bullet length is 0.85" and the nose to crimp groove length of the Beartooth 350 grain WLNGC bullet is 0.45".

I have so far loaded just one cartridge with this bullet in my 1.8" long case and seated it to 2.32" and then used my custom Lee Factory Crimp Die to crimp it on the driving band which is between the crimp groove and the grease groove.

I would appreciate it if you could look up the recommendations on Quickload if you have it. I will try later to get access to GRT. I had not heard of that before. Thanks!
 

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Discussion Starter #20
P.S. internal case length of the shortened case is 1.61" and internal case length of the full length 45/70 case is 1.915".
 
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