I'm having difficulty getting good groups from a bench rest, regardless of the load I'm using. Guns I'm using are G23 and G17. I actually shoot tighter groups off-hand than from the bench!
I know you do a lot of bench rest shooting when you're testing guns and loads...can you offer a few tips that may help me out?
IDCG, first you want a steady bench. Mine is concrete. Then, you want a good rest on the bench. For me personally, even an MTM rest is more "repeatable" than sandbags, as is the Caldwell Matrix rest I now use for most bench testing.
Get it adjusted so the frame of the gun is resting solidly in the crotch of the rest. You want the butt stabilized, either by the heel of the support hand or, with a "long-handled" handgun, allowing the butt itself to contact the rest. Recoil will bounce the gun a bit, so take time to re-set-up perfectly between each shot.
The arms need to be stabilized. On a rest, the elbows will generally be bent. Rest the elbows on the table. With a hard-kicking gun, this will drive elbows painfully into the top of the bench, so to prevent flinch, I rest each elbow on an ammo box, a folded coat, or some sort of cushion.
I've found I get the best groups with a small aiming point. ("Aim small, miss small.") I use colored dots from the stationery counter, or brown or black pasters on the white back of an IPSC target for best contrast.
If I'm aware that I've pulled a shot, I don't count that against the gun, and do a re-shoot. However, when you're shooting hand-held off a bench there's going to be unnoticed human error by the shooter. I learned a long time ago that with five careful shots with no NOTICED human error, if we measured the whole five-shot group and then took a second measurement of the best three of those shots, it allowed for unnoticed human error sufficiently to be very comparable to what the same gun and ammo would do for all five rounds out of a Ransom machine rest. Charlie Petty and I tested this for American Handgunner magazine a decade ago, and if my aging memory serves, the results appeared in the May/June 2002 issue of American Handgunner.
Hoping the above is of help,
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