I am struggling to re-create a load in .270 Win that held sub MOA years ago. I am using IMR-4350. Charges from bottom to top (55 gr). Seating depths from load manual starts to .020 off lands. Bullets have been Sierra 130 gr SPBT GameKing and Speer 130 gr FBSP Hot-Cor. Primers are CCI 200 and brass in WW. The best I have been able to get is 1.50" @ 100 yards. When this load was developed, IMR-4350 and IMR-4831 were the kings of .270 Win powders. I have not used IMR 4831. Since these are both Dupont powders, is there enough of a recipe difference in the two to make the change? Also are there more recent additions to the powder families to try? Do any of the Reloader family of powders lend themselves to .270 Win loading?

Gun is Rem 700 BDL
Load was 55 gr of IMR4350. Bullet was Speer 130 gr BTSP. CCI primer. WW case. OAL of 3.310.

Any suggestions would be greatly appreciated.

Take a look at Hogdgon's H4831SC...Some people have had good results with it. I have in my A-bolt .30-06...

I would recomend Hodgdons as well. Here's a link for there data base the charges are the same for H4831 and H4831SC the SC ( short cut) is shorter pcs and meters better. They are both part of Hodgdons Extreme powder line, they are not affected by temp change, It's supose to rock in the 270 Win
data.hodgdon.com/cartr...load_1.asp
Good Luck
Joe

You might even want to take a look at IMR7828.

The advantage of Hodgdon H4831sc is that it is temperature insensitive, at least more so than DuPont. Jack O'Connor loved IMR4831, although, by today's standards his loads were on the hot side, yet, my 24" barreled 270 Win manages 3,180 fps with H4831sc without any pressure signs. Like Bushy and shrpstrjoe I recommend trying it.

Yes, changes in powder can affect group size. The pressure curve will be different and set up different harmonics in the barrel. It is a minor thing for most rifles, however, and presumes the rifle hasn't changed over the years in terms of barrel float or bedding.

Other excellent powders are in the Reloder series with RX19 and RX22 being superb choices.

All that said, some of the rifles I like best aren't too finicky about changes in powder, bullets or velocities and shoot everything accurately. IOW, rifles that are truly particular about load differences can often be due to the rifle itself needed some attention. OTOH 1.5MOA is certainly accurate enough for the vast majority of game.

Thanks for all the advise. I have recently had the gun pillar bedded and barrel floated. That indeed may have changed the barrel harmonics. I have also had a removable muzzle break put on. I have been told that there are different opinions on if this will open up groups due to the way the gas escapes from the end of the barrel. That being said, I am testing groups with the barrel cap on (muzzle brake off)(crown has not been touched). I picked up 1 lb of H4831SC, a box of Sierra 130 gr BTSP, a box of Speer 130 gr BTSP, and a case of CCI 200 primers. Let the games begin.

Let us know how the "games" progress...

First let me say that I don't load for the 270. But, when checking the Hogdon web site I noted that WW760 and Hogdon H1000 were also listed. I have had success with both powders in other calibers. Of some interest was the H1000 load which had the high velocity and low pressure with the 130 gr bullets.

Good luck with your load work.

I use H4831sc along with 130 gr. Sierra's in my Ruger .270. In the Ruger it is a great sub MOA load. Best of luck finding a good load for yours.tr

I used to load 50.0gr IMR4831, 140gr Nosler BT, Fed. 210M primer for a Winchester with excellent results. I have since then sold the rifle.
Good Luck in finding the best recipe!
I must admit that I use Hodgdon powders exclusively now though (H4831SC, Varget, & Retumbo).

dakota 1, I used to groundhog hunt with several guys who loaded the .270 win., and they all used the same load, 56.0 grs. of IMR 4350 with the 130 gr. sierra gameking and could shoot one hole groups with that load. Nowadays there are probably better powder to use than back then, like R-22, which are less temp. sensitive, but they had good results with the imr4350 back then. The load data nowadays doesn't go that high, being lawyer sensitive, but if you increase your load .5 gr. at a time and watch for pressure signs, you might be surprised with the results you get if you just push it hard enough.

i know this may be elementary; but have you, by chance, taken all the copper out of your barrel? i have seen rifles that "used to shoot good" and the owners thought the barrel was shot out but in fact the bore was covered in copper. if you haven't taken the copper out just go get a good copper solvent, follow the directions and clean it until the patches turn from blue to clean. my dad had a 270 that was given to him and it was shooting about 4" groups and he thought something was wrong with the rifle...well it was. the barrel was full of copper...after about 2 hrs of scrubbing the copper out we took the rifle to the range and 3/4" groups materialized with factory ammo.

Suggest a good copper solvent. I have been trying to find some info on one. I just inherited a gun or two that I suspect need a good scrubbing including the copper removal.

I have used IMR4350 in my .270s for many years and have had superb results. Never saw a need to change. Someday, I may try IMR4831, but not now. All the best...
Gil

We've had excellent results with 59.5gr of Hodgdon 4831SC behind a 130gr Hornady SST. MV is just under 3,000fps & five shot groups under 3/4"
Work up to this though - it's close to maximum load.