How much velocity will I loose?

[Just Duke]

How much velocity will I loose if I have the 4 inches cut off my Marlin 1895's in 45-70?
Think it says I am at 1300 fps now.
TIA,
Duke

[VTDW]

How much velocity will I loose if I have the 4 inches cut off my Marlin 1895's in 45-70?
Think it says I am at 1300 fps now.
TIA,
Duke


You will most likely get lots of answers to that, but in my experience you will probably loose 100+ fps. Not bad at all.

Dave

[Just Duke]

OOPS! Guess I should of also said the they were Marlin SS XLR's with 24 inch barrels.
OUCH! 100 fps is a lot though VTDW.
Left you a phone message a couple weeks ago. Not sure if you got it.

[wiljen]

The general rule is 25-40 fps per inch of barrel you remove. so 100 is actually on the low side.

[Boerrancher]

It can vary from rifle to rifle but I can assure you that there will be a drop of 25 to 100 fps per inch of barrel loss. In my higher velocity rifles, 6mm-284 etc, I always started with a 26 in barrel, and tapered it so that once the throat was shot out I could cut 2 inches off of it re-thread and re-chamber it. I on average lost roughly 200 fps by removing those 2 inches. I am not sure if the affect would be greater or less on a larger bore like a 45 cal.

Best Wishes from the Boer Ranch,

[HeavyMetal]

Safe bet is 50 FPS per inch of Barrel, in higher velocity rounds it will be more.

You didn't mention if you were loading Black Powder or not?

Big advantage to the marlin lever guns is thier strength! So you can "recover" some of that velocity loss with a bit stiffer load, depending of course on boolit weight, recoil sensitivity, and type of powder your using.

[Lloyd Smale]

im with dave. Ive found ive lost very little with 44 or bigger guns.
You will most likely get lots of answers to that, but in my experience you will probably loose 100+ fps. Not bad at all.

Dave

[leftiye]

Them larger calibers with smaller cases have expansion ratio to spare, in this case - literally. If you want to know for (almost) sure, have someone run it on quickload. I'm with Lloyd and Dave, not too bad of a loss of velocity. Heavy metal is also right, if you're at 1300 fps now, you've got plenty of room to increase pressure a little and get it back.

[Johnch]

I found that in some cases , depending on the load
There can be a increase in velosity

If you are using a small charge of a fast pistol powder
The extra barrel might be slowing the bullet down before it exits

But with slower powders
You will lose 25 - 50 FPS per inch

John

[shooter93]

Big bores lose the least per inch. We built a 416/284 and jsut for an experiment we started with a 26 inch pipe. We cut of one inch at a time back to 21 inches and never lost any velocity at all.

[JeffinNZ]

I cut 6 inches off a ML barrel and GAINED velocity!!! TRUE.

The lighter loads went up in speed. The top load remained the same. Obviously the extra length was slowing things down as the charge had been burnt up alreay.

[Southern Son]

With a cast 500grain boolit, even if you lost 200fps, you will still have enough penetration to shoot through anything other than a buffalow, I don't think that there is too much to worry about.

[VTDW]

How much velocity will I loose if I have the 4 inches cut off my Marlin 1895's in 45-70?
Think it says I am at 1300 fps now.
TIA,
Duke

I remember but it got lost when I was cleaning up my directories. I am sooo technological incompetent at times. Try again.

Dave