260 rem N160 140gr

[Twdmar]

I have not found much searching so I want to ask if anyone has any info for standard 260 remington with vihtavouri n160 and 140ish grain bullets. I normally use 4831 but I do like n160 in my 6xc. Any thing good? Thanks

 

[COhunter]

Vihtavouri has reloading data on their website for a few 140 gr bullets

 

[Twdmar]

There is, sometimes significant, inconsistencies in their load data. With cartridges I have used their data with, the loads have been almost too low, even at loads listed as near max according to vihtavuori.

 

[cheng1962]

Hello Twdmar, I load 37.0 gr N160 with Hornady 140gr bullets. I get good groups at 100m. I don't have a chronograph to measure their velocity though. My 260 REM is a Pierce Eingineering action with B28 in Broughton barrel, 1:8 twist.
I also shoot 38,4 gr N150 with 123gr Lapua Scenars, I get tighter groups with those.

 

[wagonman]

I run a 260ai 28in I'm going by vv loading data for 260 rem using n160 and 43.4gr. sierra 142 2775 good accurate load, low sd very cool burning powder not suited for shorter barrels 24in or under it replaced h 4350 for me

 

[Twdmar]

I run a 260ai 28in I'm going by vv loading data for 260 rem using n160 and 43.4gr. sierra 142 2775 good accurate load, low sd very cool burning powder not suited for shorter barrels 24in or under it replaced h 4350 for me

This again makes me think the vihtavuori data is very conservative for most cartridges. I load close to 41 gr n160 in my 6xc even though the vv data states max is something like 38 or 39. When I got my new 260 out I had more 4831 than n160. Next spring I will try out the n160.

 

[Laurie]

Viht shows maximum charges in the 43 to 44gn range N160 for lead core bullets - lower for all copper Lapua 'Naturalis' and similar. Don't imagine these (lead-core charge levels) are substantially understated especially in a SAAMI throated test barrel based on the 2.8" nominal COAL. With a long-freebore match chamber allowing 2.95-3.00" COALs (or some equally 'generously' fitted factory chambers), you can run up to 44.5gn N160 in the heavier brass such as Peterson and Lapua, sometimes a bit more, but pressure often shows at around this point. Much thinner Remington brass or necked-down Winchester 7-08 cases give you another half to full-grain leeway.

N160 is a much 'quicker' powder than Viht's burning chart suggests and its behaviours are closer to the 4350s than 4831s in this size of cartridge. It also has a nasty habit of suddenly turning round and biting in the form of blown primers if you go even slightly past a given maximum level for any barrel / chamber. Also, I don't know if the latest 2020 v3.9 QuickLOAD update has adjusted N160's default values, but my older 3.6 version is WELL out. In 260 Rem / 7mm-08 size cartridges I assume it'll produce MVs QL links to 5-6,000 psi higher pressures, and therefore limit my initial top test charge weight to that which the program gives for 52-53,000 psi PMax.

 

[wagonman]

Viht shows maximum charges in the 43 to 44gn range N160 for lead core bullets - lower for all copper Lapua 'Naturalis' and similar. Don't imagine these (lead-core charge levels) are substantially understated especially in a SAAMI throated test barrel based on the 2.8" nominal COAL. With a long-freebore match chamber allowing 2.95-3.00" COALs (or some equally 'generously' fitted factory chambers), you can run up to 44.5gn N160 in the heavier brass such as Peterson and Lapua, sometimes a bit more, but pressure often shows at around this point. Much thinner Remington brass or necked-down Winchester 7-08 cases give you another half to full-grain leeway.

N160 is a much 'quicker' powder than Viht's burning chart suggests and its behaviours are closer to the 4350s than 4831s in this size of cartridge. It also has a nasty habit of suddenly turning round and biting in the form of blown primers if you go even slightly past a given maximum level for any barrel / chamber. Also, I don't know if the latest 2020 v3.9 QuickLOAD update has adjusted N160's default values, but my older 3.6 version is WELL out. In 260 Rem / 7mm-08 size cartridges I assume it'll produce MVs QL links to 5-6,000 psi higher pressures, and therefore limit my initial top test charge weight to that which the program gives for 52-53,000 psi PMax.

Sir your a wealth of knowledge I for one want to thank you for passing it along.