Effect of Barrel Length on 45/70 Velocity?

[Coltdriver]

I am going to get a 45/70 barrel for my Encore.

I have a couple of choices. One is a little short 20 inch barrel and the other is a 24 inch barrel.

I have no experience with the 45/70.

Am I right to suspect that with the slower powders you use in a 45/70 that the shorter barrel is going to lose a lot of velocity over the longer barrel??

 

[mete]

Loss of velocity is proportional to velocity.On a 3000 fps cartridge loss per inch is very significant but on a less than 2000 fps cartridge it isn't significant. My Browning 1885, in 45-70 came with a 28" barrel. I cut 6" off to make it handier and lighter for hunting .I wasn't at all worried about velocity loss !...You use FASTER powders for the 45-70 not slower ones .I've never fired an Encore so I don't know weight and balance ,that would be the only concern. If it's light you might start with the 300 gr factory loads or equivalent which have flatter trajectory than the heavier ones and are very effective on deer. ...It's a great old cartridge !!!

 

[Jackal]

From what I have been able to find out, there appears to be very little velocity gained from a longer barrel. For a nice, compact rifle, I would say that a barrel in the 20"-24" is the best.

 

[Coltdriver]

Thanks for the input. I think I am going with the 20 inch barrel. I love short rifles for field use.

As I get into this I am amazed at the range of loads you can set up for the 45-70.

Tonight I loaded some 1000 to 1500 fps rounds with unique (10 grains!) and Reloader 7 (28 grains) behind a 300 grain cast bullet. Supposed to make good plinking rounds that don't knock you over from recoil. For plinking that puts these rounds in hornet or .223 powder use territory.

I will probably use some of the leverevolution hornady rounds for hunting next year. The expansion is outstanding.

At some point I am going to try 70 grains of black powder behind one of the 405 cast bullets just for grins.

Thanks again for the input.

 

[wanderinwalker]

The 20" barrel on the Encore actually handles and balances nicely, IMO. I have one set up as a muzzleloader with the 20" barrel and so far carrying it hunting has been a pleasure. (Would really, really like to tell you how well it works on game, but alas... Of course, it IS a .50-caliber muzzleloader, so results should be excellent.)

Actually, keep us posted on how you like that barrel, because I want one for my Encore for next season!

 

[Zeke Menuar]

When I was working up loads for my 32" barreled Buffalo Classic, I found that that book data was for 22" or 26" barrels.

I came up with a figure of 15fps per inch of barrel length. So, if using data for 22" barrel I added 150fps to Speer's data and came up with a ballpark figure. Chronograph results proved this to be pretty close.

Gratuitous gun picture





ZM

 

[Gewehr98]

Depends on what you're trying to do with the round, too.

Myself, I'm quite pleased with the 32" barrel on my 1874 Sharps Business Rifle in .45-70. I don't particularly want to run smokeless loads in that classic rifle, so with a 70gr load of Goex Cartridge grade charcoal, I get around 1300fps using a 535gr Postell bullet. That's enough velocity to keep the round viable for whitetail past 400 yards, and slapping steel buffalo silhouettes out there around 1000 yards. Recoil is quite comfortable in the big Sharps.

On the other hand, my 22" Ruger #1S gets fed my zinger Reloder 7 handloads, pushing a 405gr Beartooth gas check hardcast bullet over 2100fps as measured at 10 feet by my chronograph. I'm well-equipped for anything that walks, crawls, or runs on the North American continent, but I'd better finish the job in 2 or 3 rounds worst case, because it just plain hurts on the recoil pad end of the rifle with those loads. The gun can handle it, but I cannot.

 

[Ridgerunner665]

20-35 fps per inch in the 45-70...at Marlin pressure levels (less than 40k psi).

In an Encore loaded to 50k psi...about 35-50 fps per inch.

And yes...I know its an old thread but nobody answered the question that was asked.