As said, the 55gn would be better in a 1:10 or 1:12 twist... 1:8 is better for 69gns
(My shooting buddy bought a Remingtom .223 with 1:12 twist, and the gunshop sold him some 69gn ammo... they went through the target sideways at 25 yds!!)
Any medium speed RIFLE powder will do... Something like Ramshot TAC is what I use for 55gns, and Vhit N140 for 69gns... but check published loading data...
Daryll
I have a Sako 75 in .222 with a 1 in 14 twist.. it shoots 55gn bullets, giving half inch groups at 100yards.. never tried a heavier bullet. Must be the quality of the barrel..
amc577
1:8 will enable you to use and stabilise the heavier bullets 69,75,77,80. & 90 grain
N140 gives good results
Ball powders tend to meter consistently through most powder measures where as grain type not so consistently although the LEE perfect powder measure which uses a ‘wiper’ performs very well.
You may find seating the bullet off the lands 10-20 thou improves accuracy (you’ll have to try that out )
If a magazine fed rifle then watch out for over length(magazine) as they may not fit (to long) if set off from the lands .
Other than that a cracking round out to 600yds and beyond weather (wind ) permitting using the heavier bullets .
ATB
James
The barrel is a stainless Sig Saur and is supposed to be quite good. We have a range not far away that offers up to 800m, so it would be fun giving that a go.
My friend Jon has already mentioned bullet seating depths, I'll let him help me experiment with that. It is mag fed, currently a big, daft 30 round one that just gets in the way, I have a ten round on order. I don't know if they'll accept the same lengths?
Lots of exciting testing to come
If you are new to reloading don't experiment with the bullet sitting close to the lands. This needs experience. If you get it wrong and the bullet is touching the lands it will put your breech pressures through the roof. There is also the danger of pushing the bullet back into the case that will also up the breech pressures.
Stick to factory loads and the recommended COL for now.
Stay safe and enjoy yourself.
Powder query: Vectan SP powders are from SP2 (fastest) to SP13 (slowest), they list SP7 & SP10 for .223. SP10 is for bullet weight up to 55 grains with a starting load of 20.8 grains. SP7 is for bullet weight from 60 grains with a starting load of 20.1.
I have a nearly full tub of SP8, why isn't that or the SP9 listed? Is it unsuitable, or do those other two simply cover the range of bullet weights, so they don't bother listing this?
email...... stephenbarrow@ntlworld.com