45 HPs hitting high and left

[sutherpride59]

So I loaded up some hollow point cast from my new 45 200-225grain mold. I went o the range to shoot them and see how the accuracy was and it sucked. I shot these at 10 yards off hand and they were landing 3" high and left of my normal POI. They grouped 1.9" center to center at the best. I shot them off a bag at 10 yards and it wasn't much better. I shot these out of my Beretta PX4 .45 on a nice day so what in the world. Below is all of my load data for the boolits. The ones loaded up with Clays performed slightly better but nowhere near as well as my 200 grain semi-wadcutters loaded with Clays at 3.8grains in the same gun. So my question is what the heck is going on? I know I had about 1 in every 20 didn't want to feed all the way and had to be nudged into battery. My best guess is that maybe I should try them sized to 451 and see if that's any better. I will slug the bore before I try that. What variables should I start adjusting to make this boolit fly right. Also there was no key holeing. The boolits were filled out very well, the bases were clean and neat. Could my round size be too soft by chance causeing boolit skid. I noticed the other day that some of my lead ingots got mixed together when we moved so it could Ben more pure lead than I thought.


3 batches of 100 rounds using 200 grain penta hollow point
Sized to .452"
Mixed brass
Lubed with bens red
1.23" OAL
crimped to .465-.468(due to mixed brass)
Winchester large standard/mag pistol primers
Alloy:
60% pure lead
38% WW alloy
2% Sn


100 rounds over W231 5.2 grains
100 rounds over W231 5.6 grains
100 rounds over Clays 3.8grains


Clear day, 60% humidity
Temperature of range 78 degrees
2-4 knot winds from behind


Speed calculated from 10 round groups


Average speed for W231 5.2 grains 836fps
Average speed for W231 5.6 grains 924fps
Average speed for Clays 3.8 grains 812fps

[wv109323]

The only thing I see is I would back off the crimp to .469 to .470. The 200 SWC bullet is known for it's accuracy. I would stay with .452 unless your bore slugs less than .450. I don't think your lead is too soft but I may back off the powder charge and try that. If they shoot at a lower velocity then you may have an alloy problem.

[MT Chambers]

Your alloy should be okay at .45 auto velocities, when ever I get bad cast accuracy I try a wider bullet, and keep trying until it fails the "plunk test".

[runfiverun]

I'd back the crimp off too.
I'd also seat a tick shorter.

[Cowboy_Dan]

Up and to the left? Would they possibly be moving slower and leaving later in the recoil cycle than your usual load? Can you safely go faster?

[sutherpride59]

I may have to try pushing them a little faster and see what happens.

[44man]

The only way I know to get closer to the aim point is by changing speeds and spin.

[sutherpride59]

A I'm going to try a variety of things as y'all suggested, shorter OAL. Size some to .453, drop down and speed up on my powder charge, and check my alloy I think some of my lead bars got mixed in the move and I never tested the boolit hardness so it's possible they could have been too hard.

[sutherpride59]

So to revisit this post with updates I tried these boolits out again with 50/59, 50/50 water dropped, wheel weight water dropped and wheel weight ice water dropped. I tied these all with both clays and W231. The best accuracy I obtained was 5" groups at 25 yards with 50/50 water dropped and 5.3grains of W231. Using the flat nose insert in this mold instead of the deep well hollow point one I can get 1.76" groups at 25 yards. I tried different crimps and different seating depths with no noticeable improvement. Could such a deep hollow point cavity cause too much forward turbulence? Also as a correction to my original post I'm not using the penta insert I'm using the "round" one, basically the super deep pin to make a huge hollow cavity that takes the boolit from being the normal 225 grains to 200.

[KVO]

I've been testing HP accuracy with various molds from Mihec and NOE and have been amazed how much HP affects accuracy. Same bullet profile, even virtually the same HP volume with different geometry can show a change on target. I now treat each one as a different boolit and note which HP is used along with all the other pertinents, primer, powder, size, etc. There is always the possibility that your gun just doesn't like that boolit, or at least that boolit with that particular HP cavity and load.

[fredj338]

I have never had that sort of POI shift at a mere 10y with any bullet/caliber combo in handguns. You could try a diff powder, that may have a little to do with it but 3" @ 10y is quite a bit. Since the accuracy is better as a solid, my guess is the HP cav is slightly off.

[Wayne Smith]

I'm assuming a multi cavity mold. Is it possible that you have an inconsistent cavity/pin?

[buckshotshoey]

You may have answered your own question in your original post. Did you slug your barrel yet? That has to be your starting point with EVERY firearm you intend to push cast lead through. Until we know this important dimension, it is hard to offer advice.

I don't think it is alloy related. You should be able to shoot pure lead, at that pressure range, from that .45 if it is sized properly.

[NoAngel]

If you're lazy like me you'd just aim low and right. :kidding:

[sutherpride59]

Sorry it took me a while to get back to this, I did slug the barrel for mod and my beretta at .451, it is a 4 cav so I might try casting some next week and try them in lots, 10 from one cavity then 19 from another. I am also going to try using the penta pin and see if that helps with the accuracy.

[DerekP Houston]

If you're lazy like me you'd just aim low and right. :kidding:

I'm a fan of kentucky windage too ;).

I honestly had not even tried the regular hp pin, I went with the penta pin on the same mold and it fires to point of aim for me. I'll send some to another member next week and see if he has similar results.

[buckshotshoey]

If your barrel is .451, and in your 1st post you say you are sizing to .452, this might be part of the problem. What is the size of "as cast", un sized boolits? If they are .453, try them as cast. .002 to .003 over is acceptable for cast lead. Just go back to starting loads and work up again

[lightload]

Is your crimp die a taper style?

[sutherpride59]

It is a Lee taper crimp die and I will give as cast a try as well. Again the confusion of this is using the hollow point pins I get **** accuracy, without them using the flat pins I get great accuracy from these boolits. Also to add I have tried using tight group, clays, W231, unique and just for S&Gs trail boss.

[greenjoytj]

Could the deep & wide hollow point allow the bullet diameter to collapse inward making the diameter slightly smaller? If this is occurring the bulk of the bullet length won't be at sized diameter. Instead of slugging up and getting fatter the bullet maybe slugging up by caving in getting short in length and narrower in diameter. The bullet would only need to be reduced in diameter a few thou to spoil accuracy and not along its entire length just enough to weaken the rifling grip.

[sutherpride59]

Could the deep & wide hollow point allow the bullet diameter to collapse inward making the diameter slightly smaller? If this is occurring the bulk of the bullet length won't be at sized diameter. Instead of slugging up and getting fatter the bullet maybe slugging up by caving in getting short in length and narrower in diameter. The bullet would only need to be reduced in diameter a few thou to spoil accuracy and not along its entire length just enough to weaken the rifling grip.

So far this seems to be the most likely scenario. I have a recovered hollow point I'll take my micrometer to it and see how it measures.

[lightload]

I learned a lot in this thread. It needs to be pointed out that the op has been using scientific research procedures in his testing.
From decades of reading related literature I drew the conclusion that hollow point cast boolits have an accuracy advantage. 44Man's observation about varying speed to change point of impact is a tried and true technique. Other observations by various posters have merit too. And just think, nobody got mad.:drinks::castmine:

[Scharfschuetze]

I shot these at 10 yards off hand and they were landing 3" high and left of my normal POI.

As long as the heavier bullets are grouping constantly, there really is nothing wrong with the load other than the occasional failure to chamber. Heavier bullets just tend to hit higher in the 45 ACP as the pistol is recoiling before the bullet exits the barrel. All things considered a heavy bullet takes longer to get out of the barrel or generates more recoil at similar velocities. Both factors will mean that the axis of the bore at the time of bullet departure is higher than with the lighter projectiles. The shift to the left, while not as common as vertical shift, is not out of the norm either and may be caused by your grip. I note the phenomenon routinely in all my handguns, revolvers or semi-autos. Some more than others, but almost always due to bullet weight.

The shift can be more pronounced if you are holding the pistol low down on the grip as then a fulcrum and lever situation during recoil is more pronounced than if your are holding the pistol as high up on the grip as possible.

Heavier or lighter crimps, bullet design and a .001" change in sizing is not going to impact the shift much if at all given your 3" shift in point of impact. Those factors will possibly impact accuracy one way or the other though, good or bad. Years ago I had S&W revolver sights installed on my commercial 1911 to compensate between hard ball loads (230 grain FMJ at 830 fps) to make major at IPSC courses of fire and soft ball loads (185 or 200 grain cast SWC at 800 fps) for NRA courses of fire. The shift between the two weights of bullets necessitated adjustable sights for a pistol used for both endeavors due to the change in vertical zeros.

Good luck with the project. If your pistol has a replaceable front or rear sight as I believe the Beretta does, you should be able to order different height sights to zero for each load or order an adjustable rear sight.

[buckshotshoey]

Could the deep & wide hollow point allow the bullet diameter to collapse inward making the diameter slightly smaller? If this is occurring the bulk of the bullet length won't be at sized diameter. Instead of slugging up and getting fatter the bullet maybe slugging up by caving in getting short in length and narrower in diameter. The bullet would only need to be reduced in diameter a few thou to spoil accuracy and not along its entire length just enough to weaken the rifling grip.

I was considering this also. But after thinking about it, I concluded that if it was due to a undersized boolit, they would make a pattern on the target instead of a group at 11 or 1 o'clock. I will have to rethink the advice I gave earlier. Scharfschuetze has a very interesting observation.

[DougGuy]

If you have the occasional failure to chamber fully with .452" you will have near 100% failure to chamber with .453" so I would not go larger than .452" if the barrel has not been throated. If you can dig a fingernail into the boolit you may have too much pure lead in the mix like you said. Generally 50/50+2% will work great in almost any handgun caliber but I don't know about softer than that.