pistol grouping low -new sights or me

[johnfkingmatrix]

wow strange. i do a lot of long range rifle stuff, its blowing my mind that at 10 yd a trajectory is different - how can this be? the recoil impulse before bullet leaves barrel is that different?

i usually shoot 147g and this batch is 124

 

[SSL]

One theory is "dwell time" - heavier bullets move slower and exit the barrel at a different phase of the recoil movement. One example is when people use heavy-for-caliber bullets - such as 300-grain or heavier bullets in most .45 Colt revolvers - taller front sights need to be installed in order to sight in the firearm even with adjustable sights. Obviously that isn't nearly as severe with your pistol, but 147 versus 124 might be a place to look. Those 124-grainers would be exiting sooner in the movement and possibly causing lower impact.

 

[snert]

Heavier bullets tend to impact higher than lighter ones with the same sight setting.

Lighter bullets exit the barrel of a pistol earlier in the recoil impulse, shooting lower than heavier bullets (slower). Shoot a snubby with a 130 grain lightweight bullet at a rattlesnake and be dismayed as the round hits repeatedly low compared to the 158 RN practice ammo. Very disconcerting!

 

[johnfkingmatrix]

so with a standard handgun (no snubby etc) that doesnt have elevation adjustment, if you want to shoot accurately even at <10yd ,you have to find the bullet weight that shoots poi v poa and youre stuck with that?



i run all kinds of ammo thru other pistol and have never noticed substantial deviation *cry*

 

[SSL]

so with a standard handgun (no snubby etc) that doesnt have elevation adjustment, if you want to shoot accurately even at <10yd ,you have to find the bullet weight that shoots poi v poa and youre stuck with that?



i run all kinds of ammo thru other pistol and have never noticed substantial deviation *cry*

You won't know unless you try the two different weights in the other gun too. No fighting physics.

 

[Eagle Six]

so with a standard handgun (no snubby etc) that doesnt have elevation adjustment, if you want to shoot accurately even at <10yd ,you have to find the bullet weight that shoots poi v poa and youre stuck with that?

Putting physics aside, and in the context of previous post, there shouldn't be a great amount of POI difference between a 147 gr and 124 gr load <10 yards. Now if the 147 is a standard velocity load and the 124 gr is something like a +P+ load, then that might produce a sizable difference, but it also depends on your standard of accuracy. Heavier loads compared to lighter loads will not only change the POI by internal and external ballistics, but also be effected by your skills handling those different loads.

This morning I was shooting two different handguns, with two different loads, one a semi-wadcutter and the other round ball at a steal plate at 25 yards. The plate was an 11.5" round gong. All rounds impacted the plate inside 1" of the edge. Most of my previous students as well as most of the shooters I have observed over the years would be tickled with those results. Me, my advanced students, most competitors would walk away as I did, thinking boy you better bear down as I was getting sloppy. It wasn't the different loads, it was me.

So first I would determine what my level of acceptable precision would be for the distance. That is how well does the gun shoot, 1" groups, 2" groups, 3" groups, etc. Then determine what my level of acceptable accuracy skills I have today. Can I shoot 2" groups at 7 yards with a 1" group gun, for example. Then try various loads that interest you and log the results.

Sights can be changed and that may ultimately be the solution for you. Or you may find through testing that several popular and available loads meet your minimum standards of precision and accuracy.

If the P2K in question is your carry gun, I would strongly suggest that you test with offensive loads (civilian types refer to them as defensive ammunition), rather than what most would refer to as range practice ammunition. It's a bit pricey, but if it's a carry gun you need to train with the same recoil and the same POI as you may have to defend yourself. Just my thoughts! If you are shooting and carrying handloads then of course you have the flexibility to fit the load to you and your gun.