Here lately i have been shooting about 15 shots nearly every morning. Mostly why, is to verify the second QRBP breech plug that was converted over to use rifle primers will work reliably. Each morning the shooting has begun with a cold clean barrel. Each morning the results have been quite similar. Often the first shot is the lowest shot, but not always. The target from this morning follows.
The group including the first shot measures 1/8" larger than the group measured not including the first shot. No swabbing was done whilst shooting. The only shot fired from a cold clean barrel was the first. Similar results have been happening each of several previous mornings.
Now, i have been reading this forum for years now, and i realize some will say/think that this rifle happens to be one, that puts the first shot the same place as the following shots. Many will say/think most rifles won't put the first shot with the following shots.
Last year, before hunting season started, i was shooting two other rifles that did the same as this one. The first shot from a cold clean barrel hit close to the following shots, from the fouled barrel, without swabbing. At that time i tried all kind of tricks to try and get the first shot to group with the following shots. Things like popping primers, before loading, using special regimen, and such. In the end, all the tricks seemed fruitless, and i just resorted to shooting the first shot from a cold clean barrel.
It seems i own 3 rifles that put the first shot from a cold clean barrel into the same grouping as the following shots, without swabbing, between shots. Well, i can't help wondering why. It seems to me, most shooters oil their barrels with something. Well, i don't. My rifles are cleaned with a 2-in-1 bore cleaner, which supposedly leaves a protective coating. Whether this affects the first clean shot being in the same group as the following shots...
I just don't know, but it is what i do. Me, i don't believe it is using the large rifle magnum primers, instead of shotgun primers, that has the first shot flying like the rest of the shots.