25-20 with cast 257420 bullets and IMR4227

A

Archer Sam

CGN frequent flyer
Rating - 100%
238   0   0
Location
Canada
Looking for any info that can be provided. I have at least 500 of 257420(70 gn) cast bullets with gas checks and would like to load. Problem I am having is the information I am finding on line is confusing. Some of the writeups talk about 4227. They don't specify IMR or H variety. Plus the load data seems to be all over the place.
Does anyone have developed load data with IMR 4227 they would be willing to share?
Rifle I will be shooting this in is a Savage Sporter bolt action.

Thank you,
Scott...
 
Last edited:
The Hodgdon Reloading site may have some useful data for you. Not IMR 4227, though. Bullet listed is a 71 grain LRNFP. Powder: H4227.
 
Alex McKr said:
The Hodgdon Reloading site may have some useful data for you. Not IMR 4227, though. Bullet listed is a 71 grain LRNFP. Powder: H4227.
Click to expand...

I think I saw that already. Problem is H4227 was discontinued(from what I read ) a few years ago. Some of what I read also said H4227 was a faster powder than IMR 4227 while others say they are the same thing with IMR being older. Can't seem to find anything in print on IMR 4227.
 
vagrantviking said:
I haven't used that combination myself but I bet someone here has some information about it.
https://www.marlinowners.com/threads/25-20-reloaders.26002/
Click to expand...

Thanks for this. I already had it bookmarked and read a lot of it. Here is another writeup I read where the load data is higher than other places.

http://www.lasc.us/FryxellCB25-20Win.htm

For reference, the Lyman Handbook of Cast Bullets (published in 1958) reports loading data for the 70 grain Lyman 257420 with 9.0 grains of 4227 for 1700, and a max load of 12.0 grains of 4227 for 2100 fps. (This is where it it is confusing. Doesn't say IMR or H)
 
Last edited:
I load an 80gr bullet from a custom mold over 9gr. of IMR 4227. It is the most accurate load I've found. I tried several other powders and this was so much better than anything else I quit experimenting and just stuck with it. But, every gun is different.
 
Archer Sam said:
Here is another writeup I read where the load data is higher than other places.

http://www.lasc.us/FryxellCB25-20Win.htm

For reference, the Lyman Handbook of Cast Bullets (published in 1958) reports loading data for the 70 grain Lyman 257420 with 9.0 grains of 4227 for 1700, and a max load of 12.0 grains of 4227 for 2100 fps. (This is where it it is confusing. Doesn't say IMR or H)
Click to expand...

Hadn't seen that one. Thanks
 
Archer Sam said:
Thanks for this. I already had it bookmarked and read a lot of it. Here is another writeup I read where the load data is higher than other places.

http://www.lasc.us/FryxellCB25-20Win.htm

For reference, the Lyman Handbook of Cast Bullets (published in 1958) reports loading data for the 70 grain Lyman 257420 with 9.0 grains of 4227 for 1700, and a max load of 12.0 grains of 4227 for 2100 fps. (This is where it it is confusing. Doesn't say IMR or H)
Click to expand...

It is confusing but fairly safe to assume that data is for the IMR variety. I don't think Hodgson had started making their 4227 yet at that time, and so most reloading manuals didn't specify IMR, since all of it was IMR.
 
jethunter said:
It is confusing but fairly safe to assume that data is for the IMR variety. I don't think Hodgson had started making their 4227 yet at that time, and so most reloading manuals didn't specify IMR, since all of it was IMR.
Click to expand...

That was what I was thinking to. I never assume anything if I can't find a solid answer and would rather ask and have others verify the information.
 
I have found the data in some older manuals to be a bit too hot in some loads. I always compare several sources then start on the low end and work up. I have worked on a few of those Savage bolt actions and they didn't look very strong to me, no front lock up, they actually resemble a rimfire action.
 
Data from Lyman #49:
25/20 with 86gr jacketed bullet + IMR4227 (they have data for a 65gr cast but not with IMR4227)
start: 8.0 gr
max: 10.2gr

Data from Quickload SAAMI Pmax 39000 psi
25/20 with 70gr cast, 18" bbl, IMR4227
8.0 gr : fill 63%, Pressure 9600psi, velocity = 1360fps, powder burned = 61%
10.0gr : 78%, 16150psi, 1690fps, 72%
12.0gr : 94%, 26460psi, 2000fps, 83%

It looks like IMR4227 is a bit slow for 70gr bullet in 25/20, the pressure doesn't get high enough to burn efficiently. Probably why there's not much data available for it.
 
smokinbarrel said:
I have found the data in some older manuals to be a bit too hot in some loads. I always compare several sources then start on the low end and work up. I have worked on a few of those Savage bolt actions and they didn't look very strong to me, no front lock up, they actually resemble a rimfire action.
Click to expand...
The Savage Sporter actually was available in 22 rimfire.
The Super Sporter was made in 30-06, 300 Savage, 30-30, and some others.
All had rear lock up.
 
jethunter said:
Data from Lyman #49:
25/20 with 86gr jacketed bullet + IMR4227 (they have data for a 65gr cast but not with IMR4227)
start: 8.0 gr
max: 10.2gr

Data from Quickload SAAMI Pmax 39000 psi
25/20 with 70gr cast, 18" bbl, IMR4227
8.0 gr : fill 63%, Pressure 9600psi, velocity = 1360fps, powder burned = 61%
10.0gr : 78%, 16150psi, 1690fps, 72%
12.0gr : 94%, 26460psi, 2000fps, 83%

It looks like IMR4227 is a bit slow for 70gr bullet in 25/20, the pressure doesn't get high enough to burn efficiently. Probably why there's not much data available for it.
Click to expand...

Thank you for this. The quick loads helps verify what I have read.
 
You must log in or register to reply here.
Back
Top Bottom