The UK's Finest Independent Forum for Shooters and Gun Owners. Est 2010.

Having fitted some alternative low rings (Optilocks) to my Sako 75 22-250 Varmint I took it out to zero and do some load development yesterday afternoon. Venue was the tunnel range at NCB so no issues with wind plus it is at sea level so in theory I would have a true zero to kick the development off with. Although a relatively new acquisition to me this rifle has been well used in the past, however its accuracy is always more than acceptable so I was surprised at just how poor the groups were with my new loads. I was experiencing 1" plus groups with 2 touching and one on the other side of the target spot and no matter what I tried I could not close the groups. The Viking and I spent a good hour or so discussing potential reasons for the less than ideal accuracy then all of a sudden it started to group and I finished the day with a .35MOA which at 100m is acceptable given the rifles purpose.

Then it struck me, I had thoroughly cleaned the barrel after its last outing, in fact I had scrubbed it to within and inch of its life removing every last trace of carbon or copper and I am starting to think the barrel needed to be fouled and get a bit of copper down it before it started to perform again. I have seen this with older service rifles which certainly seem to sulk if they are stripped however I have not seen this with a modern rifle and indeed all of my rifles are properly cleaned after every outing.

Has anyone had a similar experience?

I've heard this before with 22-250 rifles from two different sources. A friend who had one stopped cleaning it after a while because of the accuracy dropping off when ever he did. It was his fox rifle and he would put less than 50 rounds through it a year.

My .300 handi rifle was completely opposite. I had falling groups and tried loads until I cleaned it also within an inch of it's life, Sub 1" groups at 25yards

I also try to remove as much carbon/copper as possible after use, and before any competition I want to put a number of rounds through before starting (up to 10 max in my rifle). I think that most rifles need some fouling before they settle down to give the optimum results before they 'fall off' and results deteriorate and the number of shots needed varies between rifles. Every rifle is different of course, but that is just my thoughts on the matter.

I've experienced this with my 6.5x47. Groups are around 0.75" (100m) with a clean barrel and after I've put 20 rounds downrange it starts grouping <0.50". FYI, this is in a Border barrel which I clean with wipeout after every range day.

Maybe accuracy improves as the barrel warms up?

This is a very common problem. When I was much less experienced, I went to a 3 day competition and finished the first day at 800 yards and recorded my elevation setting. I gave the barrel a damned good cleaning in the evening then we resumed shooting the next day at 800 yds. With my elevation setting from the previous day, my shots were all over the place! It eventually settled down and I finished the shoot with exactly the same elevation that I started with!

Rule #1: Never clean your barrel during a competition!

I'm not sure what I would do during the Imperial where you're shooting for about a week, but for 3 day competitions I clean the barrel then fire about 20 rounds through it. After that, I don't clean it again until the shoot is over.

hobbesy wrote:My .300 handi rifle was completely opposite. I had falling groups and tried loads until I cleaned it also within an inch of it's life, Sub 1" groups at 25yards

With respect, 1" at 25 yards isn't anything to shout about - at 200 yards maybe!

Rockhopper wrote:Maybe accuracy improves as the barrel warms up?

I know it isn't a precision rifle by any means but my old Mosin gets more accurate the warmer it gets.

Some barrels just need a little fouling. Reasons are conjecture on the most part. Find what works and that's the recipe for that rifle.