What a poor choice IMR 4320 was for my .270

[Mustangs Rule]

What a change in powder can do, not good news.

One of my favorite old rifles is a 100% original Winchester pre 64 Model 70 standard weight in .270. It has a fixed 6X El Paso made Weaver scope restored by Iron Sight from Tulsa, Oklahoma.

It is a real classic rig. When I lived in Wyoming it was my go to antelope rifle. I had two pet loads over the years, one with 130 Hornady Spire points pushed by IMR 4350. It rarely left an inch at 100 yards off a bench.

The other load was factory loaded Barnes 130 grains. Off a bench that is a tack driver,,,,figue “8”s” and clover leaf.

Anyway,,,,the only powder I had to reload with was IMR 4320. What a disaster. I never could have believed it could have been so inacurate,,,with POI moving around like a drunken sailor.

I began to wonder if something was wrong with my rifle. I cleaned it, and fired three of my Barnes factory loads,,,,sweet cloverleaf again.

 

[greaseywater]

I've had a very similar experience in 270 with both imr4350 and imr4320.

My win70 loves that Barnes 130gr TTSX factory load. I've been trying to duplicate it. Closest I've come for both velocity and accuracy is with RL17.

 

[Mustangs Rule]

Those Barnes factory loads are pure magic in terms of both accuracy and velocity. I have given up trying to reproduce them. I have bought them in .308, .270. 30-06 and 35 Whelen.

Powder shortages have left me with only IMR 4831 an Win 760 to try in my .270 with 130 grain Speer. Have you tried those powders?

 

[Laelkhunter]

I load the Barnes 130 TTSX pushed by 54.0 grains of IMR-4350 for my .270 Win (Ruger 77). I never tried the IMR-4320.

 

[deer_shooter]

I'm sure you probably already know but IMR 4320 was discontinued.

 

[Mustangs Rule]

I'm sure you probably already know but IMR 4320 was discontinued.

No I did not know that. Thank you. I have been using whatever powder I have. I got a lot of IMR 4831.

Also pulled almost a 100 7x57 loaded rounds I no longer needed just for the W760. Glad I kept good records. Prudence always pays off, especially in reloading.

 

[Don Fischer]

I tried IMR 4320 several time's over the years and never found a load in anything worth doing again Not a clue what it is about that stuff. I guess I meant was, didn't know they discontinued it. No loss!

 

[MTLabrador]

Those Barnes factory loads are pure magic in terms of both accuracy and velocity. I have given up trying to reproduce them. I have bought them in .308, .270. 30-06 and 35 Whelen.

Powder shortages have left me with only IMR 4831 an Win 760 to try in my .270 with 130 grain Speer. Have you tried those powders?

4831 is a standard for the .270. I use H4831, but it works well with any bullet I’ve loaded in mine.

 

[greaseywater]

Those Barnes factory loads are pure magic in terms of both accuracy and velocity. I have given up trying to reproduce them. I have bought them in .308, .270. 30-06 and 35 Whelen.

Powder shortages have left me with only IMR 4831 an Win 760 to try in my .270 with 130 grain Speer. Have you tried those powders?

I've loaded H4831 under Hornady GMX. And I've done a couple of test loads with win760. I'd have to go look at my records, but I think accuracy was ok and velocity was low.