260 Reloading question

[Cedarcreek]

I just got my 260 build done and have started some testing. I am using the 123 SMK and am having some questions on the seating depth. Currently I am getting best groups at 30th off, I usually have better results with seating 10-12th off w/SMK. I have been trying to use Win 748 powder, a friend of mine is having very good luck with this in his 260. I am not sure if this is a Powder issue or a seating problem. Groups are not where they should be yet, just thinking of what the next steps should be.
Anyone reloading the 123's SmK in the 260, I would really like to hear what your favorite loads are.

Thanks in advance,

 

[navyrad8r]

i randomly chose 42gr of IMR4350 (could not get H4350) with 123 AMAX 7 thou into the lands. ,308 brass down to .260 with neck turning. i am now trying to get IMR4064 to work. i would like to use 140vld bergers, but htere is more and more talk about the .260 flying a 123 class bullet as well as a 6.5x284 flys the 140 class. except the .260 is using less powder. i am interested int he lapua 123 scenar and 120bt from berger. gonna try some more soon. i have load test set up for 142SMK/with 4064 and 12thou jump just to see. Good luck to you and please post your findings.
cheers,
doc

 

[15Tango]

748 is pretty fast for a 123 in the 260. It's probably be a better match for say, the 95s. Give H4350 a shot with them. I wouldn't expect to get great results from that powder and bullet combo (the 748 that is).

42 grains of 4350 is pretty low for a 120 class, bump it up. Hodgdon's listing 43 grains as max for IMR and 43.5 as start for H4350 and that's at 2.7" COAL, I'm sure you're quite a bit longer than that which will lower your pressure. That 123 Scenar is a real hammer! The 123 Amax is surprisingly good as well.

If either of you go with a 140 VLD you want that thing +/- 50 FPS from 2900 FPS. If you can't reach it with H4350 (which is pretty much the 'standard' for this cartridge) then try Reloder 17.

Wayne

 

[260Ravage]

I found my best accuracy with 139 lapua scenars with a light load of H4350. (40.1)
My gun doesn't like speed,,,so I just listen to it. The accuracy is superb. I tryed the powders you mention to reach good velocity and accuracy,,I stick with h4350

 

[habu]

what length of bbl? what twist?

what primer?

rough rule of thumb on bullets- most of the time - secant ogive bullets [vld] jam - 15+ thou. tangent ogive bullets [smk] on or off lands.

i started mine - 142's - on the lands and the bbl quit at 2250 - .058 off lands. fed 210m - 42+ of h4350 - 2900+ shot along side 6.5x284's - most of them ran 140's at 2950. [palma head stamp 308 brass necked down -165gr wt]

 

[BOBC]

I've been using 39grs of IMR 3031 with my 120 to 128gr bullet in 308 Win cases reformed to 260 Rem. And when I do my part, my groups are just ragged holes at 100yds. I really like the 260 Rem. I shot high power for 35years and am using my old uniform 308 cases that I used in high power for my 260. In my 50 years of shooting, I got my best groups when I jumped the seated bullets. In high power, my 308's had to work through the magazine of my short action Mod. 70 and I got great accuracy with my rapid fire rounds.
I also use 748 in my 260 Rem but prefer 3031. Seems most of the powders for the 308, work well in the 260.

 

[BOBC]

My 260 has an 8 twist 24" barrel and handles my 80 to 94gr FB along with my 107, 120 to 128 gr BT's. It likes IMR 3031,4320,and Win 748 powders. Don't know my velocities, but don't care because I shoot 10 shot groups at 100yds with the above and they all stay in half inch when I do my part. If I were a better shooter, I do believe I have a 1/3 min rifle .

 

[Cedarcreek]

I guess some more data would be helpful.
260 Nosler Brass 1st firing
Winchester Large Rifle Primers
42 grains of 748

rifle has a 26" Shilen select match w/ the chamber reamed with a match no turn chamber, 1-8 twist.

I have some IMR & H4350, Varget and 760.

For some reason I have not had very good luck with the 4350's or 760 in other calibers. I did set the H4350 out to try some test with it and see how it goes.

The OAL just seemed odd to me when I set the length closer to the lands the groups opened up. When I dropped the grains of powder the groups opened up. Temperature here has not been great for testing but I hate to wait. I am going to send a picture of the rifle later.

Thanks!

 

[Cedarcreek]

Anybody know how to add a photo to this thread?

 

[Cedarcreek]

I shot H4350 this morning and it is doing better than the 748. I started at 45.0 grains with 1st time fired brass no pressure signs and decent grouping had a .390" c-c for a 3 shot group.
The next loads I shot were from fire formed brass, they showed pressure signs on the primers. I had cratering and some blow back around the primers. I stepped down to 44.5 and still had cratering but no blow back- groups were in the .680 range for 5 shots.
I stepped down to 44.0 grains and no pressure signs and 5 shot group at .620. I will start tomorrow with adjusting the OAL keeping charge at 44.0 grains and going from there. I am going to try to stay w/ SMK 123's but if they dont work out I may have to change.

Has anyone used NOSLER Brass yet? I seem to have some loose primer pockets on a couple. Glad to hear that LAPUA is coming out w/260 brass.

Thanks,

 

[AusFclass]

I shot H4350 this morning and it is doing better than the 748. I started at 45.0 grains with 1st time fired brass no pressure signs and decent grouping had a .390" c-c for a 3 shot group.
The next loads I shot were from fire formed brass, they showed pressure signs on the primers. I had cratering and some blow back around the primers. I stepped down to 44.5 and still had cratering but no blow back- groups were in the .680 range for 5 shots.
I stepped down to 44.0 grains and no pressure signs and 5 shot group at .620. I will start tomorrow with adjusting the OAL keeping charge at 44.0 grains and going from there. I am going to try to stay w/ SMK 123's but if they dont work out I may have to change.

Has anyone used NOSLER Brass yet? I seem to have some loose primer pockets on a couple. Glad to hear that LAPUA is coming out w/260 brass.

Thanks,

i think your on the rite track with the h4350 ;D id deffinatly give the 130gr bergers a try. do you know what fps you were getting?

i have heard that the nosler brass is quite soft

 

[kentuckytroutbum]

Have you tried IMR 4320? Its kinda the "forgotten" powder, but I think it is in the "speed" range that you're looking for.

Bill

 

[sp260]

Put 43.5gr oh h4350 behind some 140 bergers vlds and go have fun quit burnining up your barrel.
I have 3 260s 2 1000 yard prone guns and a savage striker and that works great in everyone
Have fun Timp

 

[15Tango]

Put 43.5gr oh h4350 behind some 140 bergers vlds and go have fun quit burnining up your barrel.

Sounds about right to me! Seems like H4350 really agrees with Wolf primers as well.

 

[AusFclass]

Put 43.5gr oh h4350 behind some 140 bergers vlds and go have fun quit burnining up your barrel.
I have 3 260s 2 1000 yard prone guns and a savage striker and that works great in everyone
Have fun Timp

what fps are you getting with that load?

 

[Dug]

Put 43.5gr oh h4350 behind some 140 bergers vlds and go have fun quit burnining up your barrel.
I have 3 260s 2 1000 yard prone guns and a savage striker and that works great in everyone
Have fun Timp

what fps are you getting with that load?

I've seen a lot of different velocities quoted, OAL & elev diffs I guess, but I'll post mine.
142 SMK
Rem brass
Fed match primer
2.940 OAL
43.5 H4350
27.5" bbl
900 ft above sea level

2865 fps 10 shot avg

 

[sp260]

I get 2550 out of the striker 15inch barrel and 2855 and 2890
out of my prone guns. They have broughton barrels 31" and 32".
Its nice now that someone big won with a 260 Lapuas gona make me brass.
Tim

 

[jonbearman]

I cant wait for the lapua brass.I heard that mid february they are going to start shipping to dealers.Lets cross our fingers that it isnt delayed till comp season.

 

[ttfreestyle]

maybe i am missing it but having trouble finding 123 sierra match king load data for the 260 rem. plenty for lapua and Amax. thanks for any help..

 

[djtjr]

46 gn RL 22 on top of a 140 A-max just into the laands and fed 210m primer
2760 fps so a bit slower than what others are showing but sub .5MOA 10 shot groups so i am sticking with it.