How much improvenment if I set the barrel back?

[bluesman423]

Due to magazine length restrictions I must seat the bullet .120 off the lands. How much improvement in accuracy might I expect if I set the barrel back and cut a match chamber. Hopefully a tighter neck chamber and I will then turn my case necks.

The barrel is a factory Remington in 308 on a 700 SPS Tactical rifle and I am currently using a load of 43.5 gr IMR4064 with a Sierra 168 gr HPBT seated to 2.820 in Lapua brass using Federal match primers.

I can do the work myself with no problem but don't want to go to the trouble if I will not see a substantial gain in group size. A new barrel is not an option.

 

[GerryM]

That depends on how good the barrel is. If it shoots well now it should shoot better with your plans.

 

[alf]

SWAG at best. Substantial gain is subjective.

The limiting factor is still the barrel. Put a dress on a pig and it's still a pig.

Does it shoot with the bullets into the lands better?

If so, how about a Wyatts magazine box instead?

I wouldn't pay to have a factory barrel rechambered, but beings you can do the work yourself, there's only one way to find out.....

 

[clowdis]

Just a guess, as any opinion here will be, but the Sierra 168 MK "jumps" pretty darn well. My guess is that doing a setback and shortening the throat will gain you very little.

 

[NorCalMikie]

I'am thinking, load a few rounds "long" with maybe just touching or jammed into the lands, single load and see if it makes any difference. Seems like most of the 30 calibers like a jam?? You won't know till you try. If there's an increase in accuracy, think about a setback. If no change, at least you know before you go through the trouble.

 

[skeetlee]

Re: How much improvement if I set the barrel back?

I dont know much about anything but if you can do the work yourself them go for it. What do you have to loose. Whats it take to chamber a barrel. Hour Hour and a half. Sounds like fun to me!!

 

[shooter65]

put a new crown on it also