A friend asked me to do an annual check on his rifle including a "deep clean" and accuracy check, he mentioned that he thought the rifle wasnt as accurate as it was and had lost confidence in it.
The rifle is a Sako 591 in 308 and has a 4x32 Swarowski attached.
After removing 12 months of detritis from the action, bolt and bore I borescoped it and found pitting along the entire bore.
I used Wipe out cleaning products to remove carbon and copper fouling leaving the bore squeaky (but pitted) clean and went to the range using supplied ammo (fed Fusion) to do some accuracy checks.
The results were not good - circa 4 inch "grouping" - have to point out here that the rifle was standard and unbedded, it also had a "pressure pad" in the forend....
One of the test groups before any remedial work
After examining the barrel bore, I thought that nothing would assist accuracy and that the barrel would need replacing, however after discussion with my friend, we agreed that we should attempt to at least try and reduce the group size before changing the barrel keeping the rifle as close to standard as possible.
To cut a long story short, I mchined two ally pillars, relieved the stock at the forend and devcon bedded the action manufacturing a new recoil lug which was also bedded in devcon - I also recrowned the muzzle as this wasnt too crisp either.
I an attempt to retain the original rifles intergrity, I tried to mkae the improvments as "invisible" as possible
After reassmbly, I returned to the range and with baited breath commenced accuracy testing using bipod and rear bag (bear in mind 4x32 scope)
Supplied factory ammo:
Using SAMI spec 155 Scenar (my own target load)
And once scope ajusted, one shot within the 3 inch target - I had to make the dots this big due to low powered scope!!
The moral or point of the story is this - despite initial impressions that the barrel required replacement, there were other factors that needed discounting first - barrel pad removal and bedding, re crown.
The rifle now shoots very well (with factory ammo) and should satisfy the owners requirements untill the barrel is changed.
Dont immediately go for the "it needs a new barrel" option