20-250Ackley intended for 55's

[AlbertaAl]

Current project is REM788 donor fitted with 1:8 PacNor
Being delivered to a gunsmith in a few days for work to be started.

I'm supplying my own 20-250Ackley chamber reamer.

Was hoping the rifle would function as a repeater but that factory magazine is short and the 55gr bullet would have to be seated below the neck shoulder junction. I'd be giving up some powder space and is that the only downfall or what else am I missing.
Any suggestions, thoughts ?

I'm not against shooting it as a single shot and having that bullet seated to shoulder/neck junction.

In any case, I want zero free bore chambering.

[Bill K]

What was the donor chambered in, in factory form on that rifle ? If it was a 22-250 to begin with, why would it not feed the 20-250AI as well ? Just curious.

[gopher]

Just my 2 cents
Not sure how fast you want to run those 55 gr bullets but you should have plenty of fps in a AI even giving up a small amount of powder space.
The 1:8 twist seems pretty fast for 55gr bullets...why not put some freebore in it, shoot single shot and keep the option to run heavier bullets should you ever. Good luck with a neat action/cartridge project.

[Johnly]

What is the desired COL with the 55?
Is it greater than 2.860"?
A 308 length magazine might be the answer.

[Bayou City Boy]

Originally Posted by gopher

Just my 2 cents
Not sure how fast you want to run those 55 gr bullets but you should have plenty of fps in a AI even giving up a small amount of powder space.
The 1:8 twist seems pretty fast for 55gr bullets...why not put some freebore in it, shoot single shot and keep the option to run heavier bullets should you ever. Good luck with a neat action/cartridge project.

The OP is asking about a 20-250AI.

-BCB

[B23]

My 20-250 is built on a SA Rem 700 with a Krieger 8tw finished at 26in.

COAL w/55 Bergers is 2.551 at touch.

Currently, my gun shoots the 55 Berger's best with 36gr RL16 .005 off touch with single digit ES and it just makes one big ragged hole. Mine isn't a particularly super speedy load. I'm launching the 55's at just under 3700. I think other powders like RL26 would probably gain a decent amount of velocity and I may give that a try some time down the road but my current load shoots so well and with a 5-7 fps ES I'm struggling messing with it. Maybe the next barrel I'll try RL26 or other powders.

These hot rod 20's shooting the 55's aren't real long for barrel life so shooting them single shot probably isn't a bad thing. I put a HS Precision detachable mag setup in my 20-250 but to do all over again I'd just stay with standard BDL bottom metal.

[AlbertaAl]

This donor REM788 is a factory 22-250 and feeds the dummy 20-250Ackley from the magazine with no issues with the bullet seated below the neck/should junction.

Initially, I was concerned with seating the bullet so deep and loosing powder space. As someone mentioned, loosing powder capacity because of the deeper bullet seating shouldn't be a concern since the Ackley case itself makes up for that little loss.

I'll be exclusively shooting these 55 gr. Bergers and 3700 would be an ideal pet load velocity.

[Bill K]

Sounds like you would be set to go and would do just fine with that set up, even if you do seat the bullet somewhat deeper. ENJOY.

[gopher]

oops ... sorry I did not pu the 20 cal. Thats a real hot rod for sure.

[B23]

Originally Posted by AlbertaAl

This donor REM788 is a factory 22-250 and feeds the dummy 20-250Ackley from the magazine with no issues with the bullet seated below the neck/should junction.

Initially, I was concerned with seating the bullet so deep and loosing powder space. As someone mentioned, loosing powder capacity because of the deeper bullet seating shouldn't be a concern since the Ackley case itself makes up for that little loss.

I'll be exclusively shooting these 55 gr. Bergers and 3700 would be an ideal pet load velocity.

If you want to pm me your cell # I can text you a copy of the reamer print mine was built with. My reamer came from JGS has minimal throat length and uses standard 22-250 headspace gauges.