Powders/loads for 260 Rem Imp

[rstreich]

I'm looking for some powder choices and loads for a 260 Remington Improved. I'm going to be shooting 130 gr. Swift Sciroccos. I've got some H4831 SC and VV 160 on hand. Do I need to try H1000, Retumbo, or VV 165?

thanks for the help,

robert

 

[Forum Boss]

The best load I found with my regular .260 Rem was H4350 and the 123gr Scenars. With the 130s, I'd start at about 41.5gr and work up.

 

[rstreich]

Was H4350 pretty clean for you? I've grown pretty spoiled with Varget in my varmint rifles.

robert

 

[Forum Boss]

H4350 burned cleaner than Varget, without that hard-to-remove greenish residue that Varget leaves. At near-max charges of H4350, ES and SD was extremely low. Some guys were running as much as 44.0 grain H4350,with the 123s), but you really need to start low because there is considerable lot to lot variation.

The fastest I could get the 140s to go was about 2840 in a 24" barrel. In that barrel the 123s running 2960 were better ballistically.

Don't assume that the longer/heavier bullets are the best way to go until you run the ballistic numbers yourself with your actual velocities. The 120 Noslers, SMKs, Scenars, and the new Bergers, tend to shoot really tight groups too. I found it harder to get the 140s down under 1/2 MOA consistently, whereas the 120s were very "user-friendly".

 

[JeffT]

Robert,
I have a 260 A.I. that shoots very well with H4350 and 142 SMK and BR-2 primers, with Lapua brass. My best load is 42.9 which is good for 2850 fps. 43.9 shoots well also at 2950 fps but is a little stiff in warm weather, it is hard on the cases. A lot of people are having good results with H4831sc but I have never tried it, to much success with 4350

 

[rstreich]

Pretty strong recommendations for H4350 then. I'll have to pick some up this weekend. Just out of curiosity, does anyone know how it compares heat-wise? That's the down-side of Varget. It's not a big deal as this is a hunting rifle that isn't likely to see a lot of rounds, just curious.

thanks for the help,

robert

 

[rstreich]

Oh, and Jeff, got a recommendation for a neck diameter? I'm going to neck up Lapua .243 also and it looked like something around a .284 finished neck would allow for a quick cleanup skim of a couple of throusandths.

robert

 

[JeffT]

I am using a .296" necked chamber, if I was to do it now I would probably go .294" as the last 243 Lapua I bought earlier this year was .014"-.015" on the necks, the stuff I bought a couple years ago was .015"-.016" I usually go for a .003" clearence. Also, the Lapua has less case capacity than the Remington 260 stuff, so be careful when you start loading

Also, H4350 does have a higher burn temp. than the other powders you mentioned

 

[rstreich]

Checking with a proper caliper, I seem to be getting .292 necks after expanding the necks. I think I'll go for something around a .292 neck or just under. That ought to allow for a quick spin to clean up any thick spots after expanding. Wish I had a spare rig just to fireform them. Someday.

robert

 

[sbrown]

I'm having great success in my 260AI with 4831sc. I am curious as to what "trim to" length others are using for their 260AI brass.

 

[rhino]

Since the 260AI has a similar case capacity as the swede I am willing to bet that somewhere in the 49-50 grain range of VIN N560 with a PMC/Russian/Wolf Primer with a 139 scenar jamed .020 into the lands should be the kars arse.

RHINOUT!