"FastEddie" at 100+ yds groups open up to 5 inches. Cant figure it out. Loading them into the breech I feel resistance and scraping, leaving tiny metal shavings. Does anyone lube these pellets? Are the mk2's more accurate at 100 yds?
I presume this to be an ST barrel.
There are two places to look for the trouble. The breech end in the chamber/leade and the internal lip of the transfer port (if it has one). The latter can cause marks and even shaving of the head and skirt of the pellet.
The offending lip or lead deposits thereabout has to be smoothed out.
Then the muzzle end rifling of the last couple of inches of barrel should also be examined and cleaned of any deposits.
Fredrik of FX sent me a short bristle brush with which to clean the last few inches of my ST barrels, something I do regularly despite reading of others who never clean their ST rifling in those last couple of inches of barrel. He would not have sent the brush if he didn't expect me to use it.
In an ST barrel the pellets "strip" through that rifling and only pick up roughly a quarter of the rifling's twist rate. That couple of inches of rifling is nominally 1:16 inches, but the emerging pellet spins only once every 45 to 90 inches of travel depending upon pellet weight and velocity (momentum). That constant stripping of lead has to have some effect on deposits at that point. If it becomes such that the pellets get more shaved off one aspect then we have the scenario for an unbalanced flight.
The head of the second pellet shot in this video was slightly nicked and produced the result you see at 71 yards. At 100 yards that shot would have been much further out of the main group. If all pellets had been nicked they would have formed a larger group. These were shot with a conventional barrel but the same effect will prevail from any shaved pellet regardless of barrel type.
http://vidmg.photobucket.com/albums/v392/Kyogle/Kodiaks4shotsN2spiralflier71yards.mp4 Now, assuming your pellets are being damaged, the groups up to 50 yards can be quite good because the damage would have in a sense been "indexed' and so would emerge from the barrel with about the same orientation. Their spirals would be somewhat synchronized. However as the range increases, so the air currents and density somewhat changes. This results in the spirals losing their synchronization and the groups generally then become elongated or even somewhat round with a hollow center.
Of course I am only referring to very good pellets which are capable of precision shooting at longer ranges but which have been damaged. There are bucket loads of pellet makes and types that will not hold groups at longer ranges no matter what one may do to try to make them conform.
Perhaps try to give your barrel a good scrub out and check for metal lips or lead deposit around the transfer port. Chamber a pellet properly seated then push it back out with a suitable rod. You may find your answer in scratch marks or grooves in the pellet head and or skirt.
If this appears to be just "academic" then I have many SM videos I have taken supporting the response using contrived damaged pellets.
And of course there are other reasons for poor groups at longer ranges.
About the Mk 1 pellet. One of my first 100 yd groups was right on 0.50" ctc. So potentially, yes, they are accurate, though other rifles may not allow for such groups.
Kind regards, Harry.
