.308 Winchester w/IMR4227?

[oldhickory]

Anyone have data/starting loads for .308 Winchester and IMR4227?

Possible boolits are 180gr sp gc, 170gr fp gc, and 150gr rn pb.

(I got a lot of SR4756 I could use up too)

[GabbyM]

Yes. From the new 49th Lyman.
180 grain #311332 start for Unique 12.2 for 1425 at 23,000 CUP
173 gr #311041 10.0 grains 1368 fps to 15.0 grains 1813fps at 37,700 C
No data for a 150 anymore. Odly they start the 160 gr #311672 at only 9.8 grains max 13.0gr for 1646 fps. I have this bullet and the nose is tight and gets tighter as you hit the tappered front band. So I'll assume they allow for a force fit to the rifling with engraved nose. Jumping the pressure up.

[oldhickory]

I thank you Gabby, but do they have a listing for 4227?

[NHlever]

I have a .308 Ruger RL that I've been shooting, and I just happen to have a target in front of me. For the series on this target I used 21.5 - 25.5 grains of IMR 4227 behind the Saeco 180 FP. Groups at 50 yds ran from 7/8" to 1 5/8". They stayed tight through 23.5 grains, and then started opening up. With 23.5 grains 5 rounds went into just a hair under 1".

Sorry for the poor quality pictures :confused:

[GabbyM]

I thank you Gabby, but do they have a listing for 4227?

Hum. Am I getting confused in my old age or did you edit the post?
I think I got lost.

IMR-4227

173 grain #311041 - 21.5gr - 187 fps to 27.8gr - 2270 fps

180 grain #311332 - 25gr - 1867 fps to 29gr - 2126 fps

The 180 grain does show a heavier charge and they list higher pressure with the 173 grain bullet using less powder. Their data for the 311041 and 311291 is identical. They are the same bullet with a different nose.

[oldhickory]

Hum. Am I getting confused in my old age or did you edit the post?
I think I got lost.

I'll never be the one to call anyone else old or confused with all the cob-webs in my attic, but no I didn't edit my post. I think I will try Unique with the 150gr. plain base boolit though, I have some cast and won't let them go to waste and Unique looks like it would be a dandy with that one.

NHlever, it's funny you seem to settle right around 23gr. of IMR4227, that's the load I use in my pet .30/06 with the Lyman 311332 for about 1 1/4"-1 1/2" groups at 100yd. I think I'll start at around 20gr. and work up from there with the 311332 and try Gabby's suggestion of Unique loads with the old plain base 150gr. boolit.

Thanks to both of you!:drinks:

[joeb33050]

With a Savage Striker 308 Win pistol, Simmons 2-6 scope at 6X, 100 yards, 314299 ~200 gr., 17/IMR4227 in 8 5-shot groups averaged 1.916".
Two sets of 3 5-shot groups with 16/IMR4227 averaged 1.783" and 1.558".
If you're hunting or shooting LR, maybe faster is better. But for 100-200 yards target shooting, my experience is that low powder charges/slower works great. Cheaper, less recoil, less wear on the gun, quieter, etc.
joe b.

[NHlever]

I loaded both my .308, and 30-06 with 12 grs. of Unique behind the Saeco 180 FN, and was surprised that they were so close to the same speed. The .308 was just over 1400 fps, and the 30-06 ran about 1320-1350 fps. That might give you an upper limit for those plain based boolits. That load was pretty accurate in both guns btw. Both guns are ultra light Ruger's with 20" barrels.

[GabbyM]

A fellow shoots my saeco 140 grain plain base bullets from a 30-30 with 7.5gr of Unique. That is around 1400 fps or a tad over. He has great results. I'm sure you could push a PB bullet out to 1550 or so. Other than trying to keep it super sonic out to a longer range I wouldn't see much point in it. Since you can just use a GC bullet and go for it when that situation comes up. With the 140's at 1400 fps you're hitting target at 357 mag pistol energy level so it's no paper tiger.

[oldhickory]

With the 150gr. pb boolits I wouldn't mind keeping them around 1000fps. if I can do so with some accuracy at 50yds. That would make a great little pest control round for around the house and out buildings.

The gun I'm playing with at the moment is a Winchester M70 fwt which has proven rather finicky with J bullets, but is capable of fine accuracy with the right load combo, (for 3 shots at least). The loads I tried the other day were with SR4759, (what Lyman suggested for potential accuracy). They were more powerful than needed and accuracy was about 4-5" at 50yds for all loads tested. Besides, I don't have a lot of 4759, I do have several lbs. each of IMR4227, Unique, SR4756, 2400, and Herco. IMR4227 does so well in my .30/06 I would like to try it in the .308 and was disapointed that Lyman's cast boolit handbook didn't list it with any of the .30 boolits I cast.

[wyattbearp]

If you're still looking for a IMR 4227 load for .308 then here's mine:

Lyman 311644 (190 g) in Lyman #2, tumble lubed with 45/45/10, aluminum .009 thick gas check, sized to .309 by Lee push thru
Winchester Large Rifle primers
21.0 g of IMR 4227 in Lake City Brass
22.0 g of IMR 4227 in Winchester Brass

In my Remington 700, this gives 1/2 inch groups (a bit smaller if I'm having a good day) and I estimate about 1700 fps.

Let's me practice with same accuracy as my 175 SMK loads on Varget (out to 300 yards) for about a third the cost.

[sthwestvictoria]

There is factory data for IMR 4227 here with jacketed bullets:
http://www.imrpowder.com/pdf/IMR_rifle.pdf
I have used this with this website:
http://www.handloads.com/calc/reduced.asp
To arrive at loads for powder I feel is safe to reduce, 4227 and 4895 being an example.