308 Savage & copper bullet grouping problem

[mjbb1951]

I have a 308 Savage Axis that cannot seem to group non lead ammo. I have tried Barnes 130 ttsx, ppu 170 x-grom and Federal 150 copper. None of them group properly.

I have tried it with 155 lead bullets, with and without the moderator and get 1/2 to 3/4inch groups!

Any ideas anybody???

 

[Smellydog]

Have you tried the copper with out the mod?
How are the lead groups with the mod?

 

[mjbb1951]

Hi, yes have tried combinations. With lead as well and groups are sub 1 inch (1/2 and 3/4 inch)

 

[Smellydog]

So everything is fine without the mod on?

 

[Bavarianbrit]

What is the copper group/pattern size?

 

[patjack]

What powders are you using, what load data are you using, Barnes 130 ttsx are a great choice, Have you given the barrel a good proper clean worked for me in 3 rifles I use with copper.
Run them fast.

 

[mjbb1951]

So everything is fine without the mod on?

Everything is good for lead, mod or not. Hopeless with non-lead.

 

[mjbb1951]

What is the copper group/pattern size?

9 to 12 inches, no real pattern

 

[mjbb1951]

So everything is fine without the mod on?

using lead the mod has no impact on grouping. same for copper. The only difference is the lead vs copper

 

[mjbb1951]

What powders are you using, what load data are you using, Barnes 130 ttsx are a great choice, Have you given the barrel a good proper clean worked for me in 3 rifles I use with copper.
Run them fast.

I'm using Vt140 on the Barnes and the z-Grom's. Have tried to work up a load so tried 41grn through to 46grn.
Have creaned barrel before using non-lead

 

[mjbb1951]

What is the copper group/pattern size?

no real group 9inch, no real pattern. Everything is tight on the gun

 

[mjbb1951]

The Savage is 1 in 10 twist. I have used the Barnes bullets in my 308 Tikka (1 in 12) and they work just fine and have taken deer down ok.

 

[Smellydog]

So the problem is the mod then.
You imply the copper shoots ok without the mod on.
I'm just trying to eliminate the moderator from the equation.
If the copper is not shooting satisfactory with the mod off we can look elsewhere.

 

[mjbb1951]

So the problem is the mod then.
You imply the copper shoots ok without the mod on.
I'm just trying to eliminate the moderator from the equation.
If the copper is not shooting satisfactory with the mod off we can look elsewhere.

No, the mod makes no difference on or off - copper bullets are not grouping
using lead, the mod makes no difference to the grouping which is excellent (sub inch)

 

[patjack]

I'm using Vt140 on the Barnes and the z-Grom's. Have tried to work up a load so tried 41grn through to 46grn.
Have creaned barrel before using non-lead

Viht states for N140 min 43.4gns - max 47.1gns and their max is considered very conservative but a as per the normal caveat work up in your own rifle and watch for pressure signs.
Where did you get the lower than book data ? what fps are you getting when chronographed.

 

[mjbb1951]

Viht states for N140 min 43.4gns - max 47.1gns and their max is considered very conservative but a as per the normal caveat work up in your own rifle and watch for pressure signs.
Where did you get the lower than book data ? what fps are you getting when chronographed.

There is no load data available, I could find for the PPU Z-Grom bullets. I have focussed on them as they are half the price of Barnes.
The Barnes I tried 43 up to 46.5 in half jumps. but did not work for me.

I have to say that I have had probably the top 3 reloaders in my Club looking at this and they are perplexed,

 

[Bavarianbrit]

The freebore before contacting the lands might be a place to consider experimenting with, copper I read seems to like around a 50 thou jump to get the speed up. I don't shoot copper so its only what I have picked up from the net.

 

[Smellydog]

I'd just wind the buggers up until primers were flat. Measure the brass just forward of the rebated rim and measure after a shot. Less than .004" forget about it if it started to group.

Today everyone is shot scared to anywhere near book max. All my best loads and other loaders were alway roughly plus 2 gn over book max.
The data max is built around ammunition being possibly made in desert heat. Not a temperate climate only!

 

[ChesterP]

What type of bullet nose are they? Secant or VLD profile? My only thought is if VLD or even hybrid, it might be a seating concenrtricity (or lack of it) problem, cured by using a VLD type seater insert. Had this with my 6.5 and vld bullets. Couldn't work out what was going on until I measured bullet run out and found that they were miles out of spec using the standard seater plug. Switched to a vld insert and all was good.

 

[Utectok]

Need to go fast (2900-3000fps) and have a big jump (50-120thou) say about 1gr over vhit max is about right