Slow Ammo

[Reef]

I have a family member whose father passed away last year that had a fairly large selection of ammo. He had several calibers and all in the original packaging, all in very good condition. I decided to buy all the ammo and gave a fair price based on current prices with a slight reduction because I can reload most of what he had for cheaper.

In this lot was 6 boxes (120 rds), of Remington Core-Lokt 45-70 405 Gr SP, again in the original boxes and in very good condition. Earlier this week I was working up some reloads in 45-70 using Berry's 350 grain round shoulder that according to Berry's has a max velocity of 1950 fps. I decided to shoot five rounds of the Remington through the chronograph before testing my reloads as a comparison.

All five factory rounds were around 1000 fps. According to three different sources I found online, this ammo should be 1600 fps at the muzzle. Five shot string:
1040, 1053, 1011, 1022, 996

Next I shot 5 of my reloads, to 1., validate my load, and 2., see if there was something wrong with my chronograph.

Five shot string of my handholds:
1640,1653 1618, 1609, 1633

The speed of my reloaded ammo is pretty close to the load data of 1700 for the powder type and charge with the bullet weight previously mentioned.

My question is why did the factory ammo shoot so slow?

[BillM]

Was the Remington marked as "suitable for trapdoor"??

[jmr40]

Remington shows 2 loads, one at 1600 fps, one at 1330 fps.

https://www.remington.com/rifle/core-lokt/29-29473.html

My guess is that the 1300 fps load is suitable for all rifles, the 1600 fps load only for modern lever action, single shots and bolt rifles.

The old ammo is most likely the 1300 fps load and that is from a 24-26" barrel.

It isn't unusual for factory ammo to be loaded conservatively, especially years ago and with cartridges that could be fired in a rifle made in 1873. The original 45-70 loads were well known to be anemic. Lots of people think of the old 45-70's as being commonly used for buffalo hunting. They were not.

Modern loads, in modern rifles are a far different load than the ones that were available in the 1870's.

[Reef]

Yep, the box says "For use in all rifles". That must explain the issue. Thanks for the replies!

[44 AMP]

"Suitable for use in all rifles" means it will be loaded to black powder pressures and speeds, and the 1300fps range is what you get with a 405gr slug, IF your barrel is long enough.

If you are shooting that BP power level ammo from a Marlin carbine or other shorter barrel rifle you likely won't see the listed 1300ish velocity.

[Reef]

Originally Posted by 44 AMP

"Suitable for use in all rifles" means it will be loaded to black powder pressures and speeds, and the 1300fps range is what you get with a 405gr slug, IF your barrel is long enough.

If you are shooting that BP power level ammo from a Marlin carbine or other shorter barrel rifle you likely won't see the listed 1300ish velocity.

Thank you for the information. Both the remington and my reloads were fired in my Henry which has a 22" barrel.