Shining a Light on One Cause of Pistol Inconsistency

[celem]

My wife usually asks me how I shot when I return from the range. Sometimes I say good and other times I say that I had on off day. I always though that I was just having ups and downs maybe due to sleep or some other such factor. While I'm confident that there is always some variability due to health or frame of mind, today, the variability of ammunition type really hit home. I'm not a great shot, but I have fun. Anyway, my inconsistency annoys me.

Today, when I went to the range I grabbed three boxes of ammo. Each happened to be dissimilar but all were reloaded by me on the same press using the same dies.

I have attached an interesting photo of three targets - all shot within 30 minutes by me using the same Baretta 92A1 at the same distance of 10-yards. The difference is quite telling - from now on I will stick with 115g FMJ for this pistol!

Target "1" is with lead (LRN) 125 grain sized to .356, 4g GreenDot

Target "2" is with Blue Bullets (Powder Coated) 147 Gr FP sized to .356, 4.7g AutoComp (target weight marked wrong)

Target "3" is with 115 grain Precision Delta FMJ .355, 5.4g AutoComp

 

[Schwing]

These results are pretty interesting to me. Normally, when someone gets poor accuracy, the first thing I recommend is slugging the bore to make sure that the bullet diameter is not too small. In your case, the 115 grain bullets were actually smaller and more accurate which, if diameter WAS the issue, they would have been worse.


The next thing i would have checked is barrel leading. In your case, your most accurate target was last which pretty much rules out leading as causing the inaccuracy.

I have never owned a gun that was finicky about bullet weight. I am sure there are more experienced casters/reloaders who can speak to this but it looks to me like your gun just likes the 115 grain bullets.

 

[243winxb]

Barrels need cleaning before shooting another type of bullet. Lead/lube needs to condition the barrel for accuracy.

 

[celem]

Re: "Barrels need cleaning before shooting another type of bullet. Lead/lube needs to condition the barrel for accuracy."

While I didn't clean between types of bullets, I always clean after a day of shooting, so the bore started the session clean and I didn't shoot enough lead today to lead the bore. Besides, I have shot these particular lead bullets many times and never had a leading problem.

I'm not saying that bullet weight is the issue - only that the 115g FMJ shot markedly better than the other bullet types. I don't know why - just that this was a very interesting result from a simple test.

BTW - the powder coated "Blue Bullets" leave absolutely residue in the bore - not copper, lead or blue material - clean, CLEAN shooters.

 

[Jim Watson]

Organic coated cast bullets are still cast bullets.
A hard jacketed bullet can tolerate some undersize, cast cannot. I suspect those bulk coated bullets were smaller than your GROOVE diameter.

 

[james layman]

I always have a different perspective. Some bullets have different alloy. The softer have a better chance to bump up. Meaning to fill the grooves fully, giving more accuracy. I think they are less likely to lead, if tin is added. Always good to try different loads.

 

[moxie]

What works works.

 

[lauderdale]

...

 

[celem]

Thanks for all of the input. Starting tomorrow, I'll be away for a while but I will experiment some more upon my return.

 

[Drail]

On that last target you were "in the zone". And that's where you got to be.

 

[Blue68f100]

Did you ever workup the loads?

I've started many times with shotgun patterns till I dialed in the load.

Even though lead is not leading the barrel it does leave lubricant behind. To remove this it may take several magazines.

 

[ku4hx]

Targets 1 & 2 indicate need for more load development: different powder, various charge weights, different bullet diameter, different bullet lube, and etc.

A great source for information is http://castboolits.gunloads.com/forumdisplay.php?8-Cast-Boolits

 

[OilyPablo]

Very interesting. With a handgun I would have thought 99.9% it was me if I had just shot those loads in no particular order or spaced over multiple range trips. With a rifle I would know something was up. Like for example 55gr vs. 62 gr in my 1:7 DD AR barrel. Absolutely the spread is very noticeably larger with 55gr.

 

[celem]

Future tests

Upon my return from my trip, I intend to do additional testing. Next time I'll try different bullets from a bench rest. Plus, I'll clean the bore between each type.

 

[345 DeSoto]

It would APPEAR that there were two things which got "dialed in"...bullet weight and powder charge. Between a lighter bullet and a lighter charge, the bullet didn't "overpower" the rifleing. I ran into the same thing with my 22-250...55 grain bullets, "by the book" powder charge. Lightening the charge didn't seem to do much good for accuracy. Went down to a 40 grain bullet...GREAT accuracy. FWIW...

 

[Schwing]

Ok, I missed the critical part of your original post. The fact that target #3 was fmj bullets makes me suspicious that it is a bore size vs bullet size issue.

With FMJ bullets, the jacket tends to obturate more than lead bullets do. Your lead bullets will not obturate that well so, if they are undersize, you will never achieve any kind of accuracy.

I would suggest slugging the barrel (there are multiple threads and youtube videos about this) and make sure that your lead bullets are at least .001 larger in diameter. I have a Beretta 92FS that slugged at .358 so I have to size my cast bullets to .359 to get any kind of accuracy.

Your first 2 targets look very much like mine did when trying to fire bullets sized to .356 or even .357 in my .358 diameter barrel. I would also shine a light down the barrel and look for leading. If you see some, undersize bullets are even more likely the culprit.

 

[rdtompki]

And next time do a blind test. Mark the bottom of the magazines and have someone hand you the three mags in succession - no peeking.

 

[celem]

Ok, I missed the critical part of your original post. The fact that target #3 was fmj bullets makes me suspicious that it is a bore size vs bullet size issue.

With FMJ bullets, the jacket tends to obturate more than lead bullets do. Your lead bullets will not obturate that well so, if they are undersize, you will never achieve any kind of accuracy.

I would suggest slugging the barrel (there are multiple threads and youtube videos about this) and make sure that your lead bullets are at least .001 larger in diameter. I have a Beretta 92FS that slugged at .358 so I have to size my cast bullets to .359 to get any kind of accuracy.

Your first 2 targets look very much like mine did when trying to fire bullets sized to .356 or even .357 in my .358 diameter barrel. I would also shine a light down the barrel and look for leading. If you see some, undersize bullets are even more likely the culprit.

I slugged it. I had a darn hard time as, lacking a pure lead ball near that size, i used a hard lead cast, unsized, bullet. Anyway, it mike'd at .3571. I may repeat the test with another pistol that mikes .355

I agree that the Baretta's bore needs .358 bullets.

I should have suspected this because last week I shot the other pistol, the .355 bore pistol, with the blue bullets and it shot great.

 

[rg1]

A 124 Golden Saber bullet load that is very accurate in my Glock 19's when shot in my Nephews Glock 17 was throwing shots in every direction. Couldn't even tell where to hold to hit the target at 20 yards. He only shoots 115 grain jacketed loads in his but I'm just guessing that the difference was copper jacketed and the brass jackets of the GS's. Possibly if his pistol was cleaned and a few rounds of the brass jackets shot in it that it might have settled down. Was very surprised that my accurate loads shot so poorly in his pistol.

 

[230RN]

Handguns are sensitive to the way they are held. You may have a consistent hold, but minor differences in the recoil of the cartridges, including the way the bullets take up the rifling spin could make a difference in the way the gun recoils in your hand before the bullet exits the barrel.

Hence the impact point as well as the grouping may differ from brand to brand, velocity to velocity, powder burning rate to powder burning rate, bullet weight to bullet weight, and even the nature of the jacketing. Or lack of it.

 

[WestKentucky]

I have a .270 win that is weight sensitive. 130 gr no matter the make/model stack up quite nicely. 150 not as nice. The heavier and lighter bullets I have tried were terrible. There may be something to the bullet weight theory.

Try redoing your ladder test and see what that does to your groups with those lead projectiles.

 

[jmorris]

If I am going to test for groups I always bring along a "baseline" gun and ammo. I use two different .22 LR.

A Ruger MK II that can puts 10 into 3.5" at 100 yds with the right conditions (environment and me) if I am shooting pistols for groups. Or a Walther bolt action rifle that will shoot under an inch at the same distance if everything is perfect. If I can't hit a barn with either of them it is not worth waisting the ammo on testing something else.

They are also helpfull during testing sometimes. My groups will open up sometimes rather quickly if I am shooting a rifle or pistol that has a lot of extra noise or recoil. After a group with my 50 BMG, I always shoot one with the .22 before testing the next batch. Just to start fresh.

 

[mizer67]

There's something wrong with your load(s). All those groups are poor at that distance, but your lead loads are terrible.

What dies are you using? I'd venture a guess you're under-sizing the lead bullets either through seating or crimping with a Lee FCD or they're not being seated straight and you have gobs of runout.

 

[Rule3]

To many variables going on to make a statistically valid comparison. Sample size is to small also.

Different weight bullets, different types and different powder

So the results could be many different things. The best target is with a very good bullet. I shoot a lot of those . You can probably get as good a group with the other bullets just have to mess around with the powders and loads.

 

[bluetopper]

Were these benched or free hand? To me, trying out a handgun load you need to bench it at least 25 yards. I'd be embarrassed at these results and would be ashamed to post if they were shot at 10 yards.