Accuracy and OAL

Elmer

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Hi folks. Elmer here with yet another question.
What has been your experience with accuracy and OAL with handgun loads? Within the proper confines, does a longer OAL promote better accuracy, or is it the opposite, or does it matter? Your thoughts and / or experience? Thanks.

Elmer
 
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Elmer,it's OAL....... In a semi auto you have to be careful not to have the bullet contact the rifling or pressures could build. In a Revolver I'm not sure it has any effect, but be cautious if you have any recoil movement of the bullet it could tie up the cylinder rotation....
 
I have not found OAL to be a big factor in accuracy in handguns. It is, however, a fairly significant factor because it frequently affects feeding in autoloaders and, as mentioned by BB, cylinder rotation in revolvers. I generally determine OAL for a round being used in an autoloader by making sure it does not hit the lands and by making sure it feeds properly. A round too short may not feed well and a round too long may not feed well. Keep in mind that not all bullets are the same shape even if they weigh the same. Different shapes and different weights may require different OAL. Semi wadcutters are fairly easy to deal with because you need about a thumbnail thickness of the shoulder showing above the case mouth.
 
In my handguns OAL does affect reliability but not accuracy or precision, at least not to any amount that I can detect.
 
For a semi-auto:
Too long and they may not chamber (jammed into lands). I use the "plunk test" to determine the max OAL for a given gun. I like to be at least 0.020" from the lands. Then I may have to shorten the OAL to make sure they fit the magazine. May have to shorten even more to get reliable feeding. That is my procedure.

I have not played much with changing the OAL for accuracy, as I have not seen a need to. The loads are more accurate than I am, but I typically shoot at 10 yards and almost never past 25 yards.

I've heard, from someone that shoots bullseye competition, that the case length can make a difference in accuracy. Less headspace is supposed to be more accurate.
 
I had a 45 acp barrel stripped of lands and grooves and polished like a mirror. This was done to shoot shotshells in 45 WinMag brass. I loved to take that barrel, with no lands and grooves and no way for an acp case to seat other than being held by the extractor, and shoot head shots at 15 yards with it. Most of the things we get wrought up over for accuracy don't make a whit of difference at 10 or 15 yards when the target is head size.
 
Elmer,it's OAL....... In a semi auto you have to be careful not to have the bullet contact the rifling or pressures could build. In a Revolver I'm not sure it has any effect, but be cautious if you have any recoil movement of the bullet it could tie up the cylinder rotation....

Thanks BB for the correction.....I have made the changes.
Thanks, as well, for the caution.
What prompted the questions is that I've read a few articles lately equating different bullet seating adjustments with better accuracy and, while my loads are fine for what I do with them, I could always use some help.
Thanks again.

E
 
I have not found OAL to be a big factor in accuracy in handguns. It is, however, a fairly significant factor because it frequently affects feeding in autoloaders and, as mentioned by BB, cylinder rotation in revolvers. I generally determine OAL for a round being used in an autoloader by making sure it does not hit the lands and by making sure it feeds properly. A round too short may not feed well and a round too long may not feed well. Keep in mind that not all bullets are the same shape even if they weigh the same. Different shapes and different weights may require different OAL. Semi wadcutters are fairly easy to deal with because you need about a thumbnail thickness of the shoulder showing above the case mouth.
Thanks Charlie. How would you go about adjusting OAL for a FN bullet if all you could find was load data for a RN (both bullets being the same weight FMJs)? That happens to me now and again.

E
 
For a semi-auto:
Too long and they may not chamber (jammed into lands). I use the "plunk test" to determine the max OAL for a given gun. I like to be at least 0.020" from the lands. Then I may have to shorten the OAL to make sure they fit the magazine. May have to shorten even more to get reliable feeding. That is my procedure.

I have not played much with changing the OAL for accuracy, as I have not seen a need to. The loads are more accurate than I am, but I typically shoot at 10 yards and almost never past 25 yards.

I've heard, from someone that shoots bullseye competition, that the case length can make a difference in accuracy. Less headspace is supposed to be more accurate.
Okay, so the real issue with OAL for most of us, aside from pressure, is reliability and not accuracy? Do I interpret that rightly? Thanks.

E
 
As with any new bullet profile, I do some trial and error testing to find out what feeds and fits into the magazine. I start a bit long and keep going shorter until it works. If I had to seat the FN bullet deeper, the powder charge would be reduced a bit and worked up to make sure I do not get excessive pressures.
 
As with any new bullet profile, I do some trial and error testing to find out what feeds and fits into the magazine. I start a bit long and keep going shorter until it works. If I had to seat the FN bullet deeper, the powder charge would be reduced a bit and worked up to make sure I do not get excessive pressures.
Ah, I see. Thanks Charlie.

E
 
You're right, of course. My big accuracy problem is Me!

Thanks BatteryOaksBilly

E
Elmer, you are most welcome. We all suffer from that problem. I have known 2 men in over 50+ years of shooting who could outshoot a box stock gun...2! Sometimes we all fall into the problem of over thinking things. You have valid questions concerning OAL, I mean HELL, if it won't go in the mag, what are we to do with it? You will eventually come to some standard loads for each of your weapons and then you can concentrate on burning them up so you can get better. I am blessed that I can and do shoot every day. I have reached a point in my life where I can see a degradation in my skills. From this point on I'm Not going to get better, but I ain't quite dead yet.
So, to answer your OP, unless you are going to be a serious pistol shooter, say a 2700 shooter, there are variables that will help with holding the X ring at 50 yards. However, any informal shooting you are involved in won't be hindered by OAL for lack of accuracy.
 
@BatteryOaksBilly
Yeah, it's sad what happens to skills in one's golden years. Most of mine have gone wherever my hair went. I just took up reloading in December of 2017 as a hobby after retiring. I read a lot about it several months before actually trying it out but have discovered that cognitive skills diminish right along with everything else. Being able to ask here and get answers I can trust makes all the difference. So, thanks again to you and all the fellows.

Elmer
 
Thanks Charlie. How would you go about adjusting OAL for a FN bullet if all you could find was load data for a RN (both bullets being the same weight FMJs)? That happens to me now and again.

E
I will jump in here.

If I am using a new (to me) bullet, I will use the method I mentioned previously to figure out the best OAL for my gun. I make dummy rounds for that, and manually cycle the gun to see that they will feed properly. You will probably find that FN bullets will have to be seated shorter than RN bullets to "plunk", especially if they are conical.

Plunk test:
http://www.shootingtimes.com/reloading/reloading-tips-the-plunk-test/

Once the OAL is figured out, the you need to find load data. It is my opinion that the important dimension for load data is where the base of the bullet resides when seated, not the OAL. I figure out where the base of the bullet resides (think case volume). Then I will go searching for load data of bullet with the same general construction and weight, that will have the base of the bullet close to the same location, or slightly deeper. (Increasing volume is safer than decreasing volume). The only way to figure this out is to know the length of the commercial bullets, and performing a little math. I keep a spreadsheet with the lengths of all the bullets I have in inventory, and the required OAL of each for my guns. Sometimes I find something close that I have already used, and I start there. (I still start low and work up, though). If I don't find what I need there, I go here:

http://www.jbmballistics.com/ballistics/lengths/lengths.shtml

Okay, so the real issue with OAL for most of us, aside from pressure, is reliability and not accuracy? Do I interpret that rightly? Thanks.

E
For semi-auto handgun, that has been my experience.
 
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So, trimming brass in pistol loads is a good thing. Yes?

Thanks
E

To answer that question, simply look at all the tools available for trimming auto pistol brass.

Pistol brass typically shrinks in length, not grows.

Now, if you are loading bullets with a crimp groove, then trimming the brass will allow for a more uniform crimp from piece to piece. Normally revo magnum calibers.

I don't know anyone who trims auto pistol brass. That said, I bet someone out there does it.
 
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I don't know anyone who trims auto pistol brass. That said, I bet someone out there does it.

You haven't met ME yet,,,, I DON'T trim my practice (go bang) brass cause the range is short and the target is large. HOWEVER, when I switch to the precision stuff it ALL gets trimmed because I need the utmost in accuracy and reliability.
Combat practice versus Bullseye scoring where 1/4" shift can cost points that cost money....
 
Just for curiosity, how does trimming auto pistol brass effect headspace?
You are effectively changing headspace by trimming, correct?
Possibly relying more on the extractor for an assist in keeping correct headspace?
 
In an semi auto pistol the "head space" is measured by the moment the barrel goes fully into battery AND the case mouth hits the shoulder in the barrel. Having those 2 come together at exactly the same time is fairly difficult.
IF the barrel isn't locked but the case mouth is bottomed in the barrel the case is obviously too long and needs to be trimmed.
IF the barrel is locked but the case isn't bottomed on the rim inside the barrel misfires can occur since the round is too short.

When I load for my Target .45's (2 Colt Gold Cups and 2 Combat Elites) I take note of the length that each gun prefers and allows it to lock up and function correctly. Only 2 of the 4 guns can use the same OAL, the other 2 need different dimensions. I know this may be a little too anal for most folks but it gives me what I'm after, accuracy!!!
 
Invaluable information guys. Thanks a million! Now, if I can just wrap my head around some of it....that's the challenge.

Elmer
 
In an semi auto pistol the "head space" is measured by the moment the barrel goes fully into battery AND the case mouth hits the shoulder in the barrel. Having those 2 come together at exactly the same time is fairly difficult.
IF the barrel isn't locked but the case mouth is bottomed in the barrel the case is obviously too long and needs to be trimmed.
IF the barrel is locked but the case isn't bottomed on the rim inside the barrel misfires can occur since the round is too short.

When I load for my Target .45's (2 Colt Gold Cups and 2 Combat Elites) I take note of the length that each gun prefers and allows it to lock up and function correctly. Only 2 of the 4 guns can use the same OAL, the other 2 need different dimensions. I know this may be a little too anal for most folks but it gives me what I'm after, accuracy!!!
The highest aggregate ever fired at Camp Perry for the National Matches was shot by CPO Don Hamilton in 1969. It still stands today. This with iron sights only. All the king's horsemen with all their optical sights have never beat his score. With all the advancements made in pistol shooting, nobody has ever beaten his score Amazing! Also remember a man with a 32 inch sleeve holding his gun with one hand shooting iron sights sees his front sight of .125 inch cover 17 INCHES of a "bull" at 50 yards. Include the light bars on either side and now we are covering 22 inches on the target. SO, it is optically impossible for men to do what they regularly do. This requires unbelievable dedication to this endeavor. NOBODY has ever shot a perfect 2700 score in all the years of competition. Indeed men who break into the 2600s are rare indeed.
In over 40 years of competition shooting I have noticed that 2700 shooters can shoot successfully in any shooting discipline, the opposite does not happen. Go to YT and watch the great Rob Leatham at Camp Perry. He has a wonderful time but does awful. 2700 shooters are THE cream of the crop in pistol accuracy shooting. If you have never tried it PLEASE do. It will put ALL other shooting sports into perspective for you.
As a side note...I own CPO Don Hamilton's centerfire pistol. It will be here for all to shoot in October.
 
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