Hey guys,

I am looking at building a 7x57 to shoot bullets on eith side of 140. Most will be cup and core but may shoot 140 gr. Accubonds or Barnes for larger game. What twist would be best?


Thanks,

ddj

9 or 9 1/2 or 10 inch twist will work with 140 gr.

C.I.P. (Euro) twist is faster than 9", for the 175 gr bullets.

I have a 280 with a 10" twist and it shoots 140gr bullets very well. If the heaviest bullet I planed to shoot in 7mm was 140 gr, I would choose the 10" twist again. For 160 gr, I would go with 9" twist, which should work for lighter bullets too.

KB

Mine wears a 1:8 twist PacNor select match and shoots 140gn GMKs, 150gn GMKs, 162gn Interlocks all to the same point of aim and all in the same hole. 7x57? yeah, it really stinks!

My Ruger No.1 is a 1-9 twist and shoots 145 Speer HC's into ragged cloverleafs.

It also drops 175gr. RN's into sub 1" groups.

I have little need for better out of this rifle.

I agree with the 1 in 10 or 1 in 11 for the bullets south of 140. Just like I prefer 1 in 11 or 1 in 12 for my 308's. The difference is really marginal until you get into the higher 500 BC's.

I have the 120gn GS Customs and the 160gn Woodleighs as my bullets of choice to cover the spectrum and they both work exceptionally well in my 9 in twist 7x57.

Von Gruff.

From now on I will stick with the 9" twist for 7mm barrels. I have tried two different custom rifles (a 280 and a 7x300 Wby) with 11" twist and neither shot very well for me - even with 120 or 140 gr bullets.

Just the thread I needed.
Have a 7x57 Zastava with 1:8 twist on lay by. plan to start at 140, go upto the RWS TUG in 190 ,I think. Whats the opinion/advice?
TIA

190gn bullets are too heavy to be practical in the 7x57. They made thier reputation with 140 to 173gn weights but IMHO with the bullet deveopement that has occured in the last 25years in particular ( GS customs and thier like) the lighter weights are exceptional performers while the 160gn C&C bullets like the Woodleigh are still about the best as all rounders. With your 8in twist I would think the 160 - 175gn weight would be the best.

Von Gruff.

In my 280AI I have a 1:8 twist and it shoots everything from 120 up to 168gr(heaviest I have tried so far) exceptionally well. It might be better suited for the heavier bullets but so far it hasn't had any trouble shooting the lighter bullets.

If you ever want or need (lead free area of Cal Peoples Republic) to uses GMX's then get the fastest twist you can. I ran the numbers on a 6.5mm GMX(1.4" long)and they take 1/8" twist. Hornady makes you e-mail them or buy to find out their bullet lenghts. I don't know what the factory twist was on 264 Win Mag barrels but if it wasn't 1/8" then no factory made 6.5 would stablize it. On my balistic program I ran the bullet up to 4400fps and it still needed 1/8". If the bullet didn't have that boat tail(need to worry about that 3"less drop at 600yds) then it would work in 1/9". Finman: what is the lenght of your 7mm 140gr GMX's?

Thanks guys.

I think I am going to order a 3 groove 1 in 10 twist barrel. My barrel maker is going to use a shorter reamer so 175's will probably be out so I think the 1 in 10 will suit me best.


ddj

quote:

Originally posted by Fat_Albert:
... Finman: what is the lenght of your 7mm 140gr GMX's?

Haven't the foggiest my friend, so long as they all end up in the same hole down range and drop the animals I hurl them at, I never thought to measure them...I just went to the shop and bought all they had, which, incidentally, is not much since there ain't much brass crossing the Atlantic of late...

best wishes,

Finman

Von Gruff: You need to publish a list of practical bullet weights for all cartridges so we will all know. I asked jeffeosso to publish a list of cal=cartridge because he can tell you what cartridge people are posting about by just having the caliber. Ps: To everone who is trying different bullets to see what works in their gun should check out this site. They sell bullets (17cal to 30cal at this time) at a per-bullet price. If you are trying to find out if a bullet will work with the twist in your gun, you should be able to tell with 12 rds. It looks like the bullets cost about double the whole box price but you don"t get stuck with 88 bullets that don"t work in your gun. http://www.bulletsamples.com/