Yep, even after patching it out with dry patches...
Cold bore vs fouled rifle bore POI
- Thread starter logan1080
- Start date
Yep, even after patching it out with dry patches...
i went out yesterday tot he range, remington 700 in 30.06. using 150 gr ammo. first shot out to 100 was about 2 inches left and 2 inches down, second shot was closer, third closer, by the time i put 5 or 6 through i was hitting dead center. mine always shoots like that, after it gets fouled its fairly accurate. i put close to 100 rounds through it one day and my groups were starting to open up at that point. guess she got too dirty. but everything in between was great
I decided to run a little experiment. The barrel had about 300 rounds on it since the last cleaning and in the last shooting session I got caught in the rain. I've noticed that this always seems to wreak havok in my next shooting session if I don't clean in between. If you look at cases that have gotten wet a few days after, they always seem to have a light blue or white powdery substance in them, at least with Hodgdon Extreme powders. I suspect that is the culprit.
This is 308 Win., 190 SMK, 42.9gr. Varget fire off of a Harris bipod.
The left group includes the CB shot with a dirty bore. The right one includes the CB shot right after cleaning. All are 5 round groups.
Velocities were:
1st group w/dirty bore:
2537
2524
2530
2518
2524
2nd group w/dirty bore:
2526
2535
2514
2552
2529
1st group w/ clean bore:
2489
2517
2520
2513
2512
So, there was a clear POI shift after cleaning. And the first round after cleaning was noticeably slower than the shots that followed, but still groups reasonably well with them. The rifle was still zeroed from NSCC. And there is also a clear difference between the 100m zero I obtained at Connaught and the 100y zero at the local club. My groups after cleaning are usually touching the dot.
This is 308 Win., 190 SMK, 42.9gr. Varget fire off of a Harris bipod.
The left group includes the CB shot with a dirty bore. The right one includes the CB shot right after cleaning. All are 5 round groups.
Velocities were:
1st group w/dirty bore:
2537
2524
2530
2518
2524
2nd group w/dirty bore:
2526
2535
2514
2552
2529
1st group w/ clean bore:
2489
2517
2520
2513
2512
So, there was a clear POI shift after cleaning. And the first round after cleaning was noticeably slower than the shots that followed, but still groups reasonably well with them. The rifle was still zeroed from NSCC. And there is also a clear difference between the 100m zero I obtained at Connaught and the 100y zero at the local club. My groups after cleaning are usually touching the dot.
