OAL

[wingnut]

Does OAL effect accuracy and if so do I want to be longer or shorter. Ibejihead 147gr 3.9 WFS at 1,140oal 379 crimp 132 PF ES is 26 SD is 8 so the on line calculator come up with. This load is for uspsa and 3 gun.

[Sarge]

You have to do load development to see what works in YOUR gun. Some guns are much more accurate with a shorter than max oal while others like to be stretched out. Then change bullet brand, type, weight, etc and test again. Change powder type or charge weight and do it all again.

[wingnut]

gun is CZ spo1

[gng4life]

You really have to work out and test the loads. In general, my 1911/2011 style guns normally like longer OAL while my striker fired pistols are the opposite but that is just a general statement and not absolute. That's the fun part of reloading, testing many combinations to find the perfect load for you and your gun.

[BMaus]

..

Edited July 5, 2015 by BMaus

[BMaus]

A friend did some testing and found that shorter was more accurate in his Shadow.

I am running OAL of 1.095 using 135gr LRN in my CZ 75 SP-01 Shadow Aus

Going shorter will up your PF a little.

Edited July 5, 2015 by BMaus

[CZinSC]

Test your gun. Only way to know for sure. I had an SP01 and longer was better to a point. I loaded MG 124 FMJ's from 1.125 out to 1.165. 1.150 was the best. You will see tons of guys that say shorter is better. Ask them if they actually tested. BMaus above says he and his friend tested and shorter was better, so that is good, but as you can see i tested and longer was better. Test your gun.

[Steve RA]

Do the "Plunk and Twist" test as you load longer and longer and when a cartridge fails the test one loaded about .005 is the longest you can go. Try a few of them in your mags and make sure they fit and feed. If the accuracy doesn't suit you then you can work shorter and see if it improves. It's very rare that you will find two barrels that will accept the same length in loaded cartridges.

[IDescribe]

With rifle calibers, the tendency is for accuracy to get better the closer you are to engaging the lands, if not outright engaging the lands. With pistol calibers there doesn't seem to be such a tendency. There are many possible reasons this might be true, but at the end of the day, with pistol, you'll need to test to determine what is best with a given combination of components, and if you change a component, you should probably retest.

Two considerations:

One -- If we're talking about accuracy at 25 yards or less, it might be difficult to detect with certainty the difference in accuracy between several exceptionally accurate loads, so if you get a load that's producing exceptional accuracy, it might be wasted labor to try to improve it.

Two -- There's typically more difference in accuracy from one bullet to the next than there is from one OAL to the next, so if you're shooting these bullets and they're not meeting your expectations, it may just be that they'll never work for you (or for you in that particular pistol) as well as what you were shooting previously.