3 shot pattern info needed

[Martind16]

George: I have a 1974 Browning BAR semi-automatic 308 in excellent condition. I beleive that this rifle has not been shot very often. I purchased it in the fall.

I have been doing my own reloading for about 30 years. In my other lever action Winchester 308, I reload with IMR 4320 powder at 41.0 grains with a 180 grain Nosler Partition.

In my lever action, for 30 years, I consistantly got a 3 shot grouping within 1 and 1/2 inch circle. Yes the barrel was bedded.

With this Browning semi, same load structure, the 3 shot grouping is as follows:

The first shot is always lower than the other 2 in the grouping by 2 to 2 1/2 inches and the 2 remaining shots are always tight within a 1 and 1/2 inch circle.

The chart tells me that with the 4320 powder and the 180 grain bullet, I could go to 44.0 grains

Could you please advise a starting point to bring this circle on a 3 shot grouping closer.

The barrel has a single point contact to the stock (floating) and there is not wood contact to the barrel except under the chamber. The barrel and moving parts are clean with very little lubricant.

Your help would be appreciated.

Thank you,

Gordon

 

[RoadkingLarry]

I'll see something similar with handloads in my 1911, first round hits different POI than rest of group (not significant enough to be an issue for SD purposes). It is my understanding that this is due to minute differences in "battery" position between a hand cycled slide/(bolt) and one cycled from firing.


This thread might go over better in the general forum

 

[CrawdaddyJim]

Is the first shot to point of aim? If so, then it will do the job in the field. The BAR rifles I have owned were prone to quickly heat the barrel and as such made for poor grouping. But I never missed a animal do to the gun's fault.