Cast Bullet Keyholing and Tumbling

[ChrisG]

Hi All,

I am new to the forum but have been casting for about 10 years now. I have been casting the Lee 310 GC boolit sized to .431 for my 4" Ruger Redhawk that I just bought 6 months ago, and loading it with a 19.0 grain load of Alliant 300 MP (Well below even the 10% under max rule). I started with 19 grains of H110 and got yaw so I got the 300 mp to slow down the burn thinking it would solve the problem. Anyhow, 4 out of 5 bullets are still keyholing at 15 yards and tumbling at 25. The throats of the gun are .431 and the bore is .430. I am not getting any spitting and it looks like the bore is fairly well aligned with the cylinder. If it is off, it is not off by much more than a couple thousandths. The gun seems to shoot the bullet well with a light load of trailboss at about 620fps. But anytime I go to a magnum powder I get yaw or just a complete tumble. I thought maybe it was the pressure curve so I even tried HS-6. With 13 grains of HS-6 (about 900 fps) I still got yaw but not quite as bad. I know people are going to suggest the crown and leading but neither is a problem.

I am getting to my wits end with this. The bullets are cast of quenched range scrap. I am not sure of the BHN but they are not easily scratched with my fingernail. The only thing left that I can think of is that they are too soft and when pushed at 30,000psi, the rifling strips off the bullet and doesn't stabilize it. It is gas checked so I thought that wasn't easily done. I know there are people here who have a lot more experience than I do troubleshooting this sort of thing. I bought some foundry lead (23% Antimony and 12.5% Tin) to mix in and see if that hardens it up. Is there anything else I can try?

Thanks for any advice.

[Tim357]

Have you tried pushing them harder? Perhaps they need more rpms to get stable. IMO and IME heavy projectiles need more spin to get and stay stable. Have you tried a 240-250gr boolit for comparison?

[44man]

Need to spin. My load with the Lee is 21.5 gr of 296 and a fed 150 primer. The boolit has proven accurate beyond 200 meters.

[oteroman]

Vary crimp. Easy to do.

[ChrisG]

Hi Guys, Thanks for the replies. Yes I have 240 grain cast boolits but I only push them to about 1000fps. They seem to shoot pretty well. About the spin rate, according to the Berger spin calculator and the 1:20 twist in the rugers barrel, they should stabilize down to about 200 fps. My own loading bears this out. I loaded these with trailboss to 620fps and they seemed to stabilize just fine. I have shot 180 grain .358 cast boolits in a GP100 1:18.75" .38 special at 550fps and had them stabilize just fine so a bigger diameter bullet that is only slightly longer shouldn't have a problem stabilizing at 900 fps.Thats why I am so puzzled.

[ChrisG]

Vary crimp. Easy to do.
Are you saying I should go with more or less crimp? Because currently they are crimped pretty good so that they don't jump and bind the cylinder up.

[oteroman]

Not knowing where you are now hard to say. Test 10 rounds with a bit more crimp, then try less, but test for no bullet setback.

[ChrisG]

Thanks! I will give it a try!

[44man]

Crimp should only be folded to the bottom of the groove, More will buckle brass and ruin case tension.
NO, NO, a heavy boolit will NOT shoot at 200 fps. The 310 needs around 1300+.
Toss the charts and figures.

[runfiverun]

umm obvious question.
but you are using gas checks right?

[ChrisG]

umm obvious question.
but you are using gas checks right?
Yes I am. Hornady .44 gas checks to be exact. I'm going to try and catch a bullet to examine. I'll slow it down with some wetpack and then sand.

[osteodoc08]

There is no way that boolit would be stable at 200 fps.

As 44 man suggests, step up the velocity. Get a good GC boolit and put the throttle
down with some 296.

[runfiverun]

un-stabilized boolits are caused only by one thing.
the boolit isn't spinning fast enough.

if the twist is on the slow side you need enough velocity to make up the difference.
if you have enough twist and velocity then you have skidding so the boolit isn't engraving the rifling properly.

I think I'd try going faster as my first step with the slower powder.

[randyrat]

I run that bullet (Super Red Hawk) gas checked with WW or softer a little hotter, 21 grains of H110 and get no tumble or leading. I think that bullet is long enough to get by with a softer alloy. It's a Thumper!
If you go softer, be sure you are not sizing the bullet down when you seat it, in other words, be sure your expander plug is fat enough for cast.

[Mal Paso]

Are you chronographing your loads or going buy the load chart? Alliant used an 8.25" test barrel and as slow as 300-MP is a 4" barrel will produce a lot less velocity.

When I tested I was using a 250g NOE 429421 and never got close to the performance Alliant stated with my 4 & 6 inch guns.

[ChrisG]

Are you chronographing your loads or going buy the load chart? Alliant used an 8.25" test barrel and as slow as 300-MP is a 4" barrel will produce a lot less velocity.

When I tested I was using a 250g NOE 429421 and never got close to the performance Alliant stated with my 4 & 6 inch guns.

I am chronographing the loads. I'm going out today to try 5 different loads for speed and shooting them into tightly backed paper for evidence of yaw. The loads are as follows:

Lee 310, 6 grains trail boss
Lee 310, 13 grains HS-6
Lee 310, 20 grains 300 MP
Lee 240 RN, 9.5 grains Unique
Hornady 240 XTP, 23.5 grains 300 MP.

I tried to vary the loads as much as I can to see what seems to work and what doesn't. I also crimped the first three enough to curl the mouth into the crimped groove and the last two with as little crimp as I can get away with. I will update the thread when I get back later. Thanks for all the suggestions so far!

[44man]

I think MP 300 is too slow, can't get enough in the brass.
My home made boolit weighs 330 gr and has done this at 200 yards. 21 gr of 296 and a Fed 150. 168567168568 However taking it down to 1100 fps does this at 50 yards.
My sweet spot with the Lee is 1316 fps. Fantastic deer boolit.
It takes very little velocity loss to change things. I can see even 50 fps changes.
Use of a magnum primer in the small case will move a boolit and increase air space before the pressure can build with slow powders.
Even with a 330 gr, you can see the case tension I use, look at my loaded round. Python with a cow inside! Crimp does nothing for burn, only need enough to aid tension so boolits don't pull from recoil. The wrong primer can still break my heavy boolit loose as will a slippery lube.

[Sasquatch-1]

Is this a used gun? Could the barrel be heavily leaded? The only other thing is an undersized bullet. Have you slug the barrel and chambers?

I have a Redhawk 7.5" barrel that I shoot 240 to 260 grn bullets through. I use 7grns. Unique pushing around 750fps. Makes for a accurate and pleasant to shoot round. When loading 110 or 296 it is full bore at 21.5.

[stubert]

Listen to us, that 310 grain needs to go faster. Forget the crimp, forget the crown, go buy some 110 or 296 and have fun. I shoot that bullet in a 7.5" Redhawk with 20.8 grains of 296 seated to 1.71.

[ChrisG]

Thank you for all the advice everyone. I got home from the range on Saturday (My friends back yard) and everyone who is telling me it needs to go faster is probably right (yes you can all pull an "I told you so"). The boolit looked perfect. It definitely skids a bit when slamming into the rifling, but by no means is it a lot. I went back to the loading bench and loaded up some 21, 21.5 and 22 grain charges of 300mp (sorry I know everyone says I need you use H110, but it is all I have for now until I go to the shooter's supply) I am going to try them out sometime this week. The best shooting load I had was the 20 grains of 300mp. I couldn't tell if it was yawing, but when I found it in the box of sand, It showed some deformation on the nose. In order for that to have happened, it would have had to pass through 2 feet of water & wetpack, 6 inches of packed cardboard and slammed into the sand nose first. To my mind that means it must have either been a) a fluke or b) been relatively stable so as to not tumble through all the barriers.

BTW, even at the 1000 fps that it was travelling, It still almost punched through the foot thick box of sand after going through all of the previous barriers! This thing penetrates! Not as well as my .375 H&H with Solids, but still pretty impressive!

[fredj338]

I get good accuracy with the Lee 310gr gc down to 1000fps in my m629 3", never tumbling. At 1200fps in the ruger BHB, for me, good 3" accuracy @ 50yds.

[ChrisG]

Well, I just got home from shooting my test loads and both of them shot better. Chronoed the 20.5 grain charge and it ran about 1125. The 21.5 grain charge ran 1175. No pressure signs. Bullets still not hitting dead on but consistently slightly off to one side. Just checked my bullets and they are slightly out of round. I am wondering if this is causing bullet wobble? It is likely a result of lapping my mold.

[44man]

It is very hard to lap a mold but I don't think it is the problem. You are using less MP300 then a 296 load so you are still too slow. I don't know if a highly compressed load of MP300 can reach what is needed. You really need at least 1300 fps. You are shooting Unique velocities.

[runfiverun]

are they bigger than your barrel/size die/throats?
if so they are coming out of it round.

you might be damaging the boolit somewhere in the process.
it doesn't have to be O.O.O. to be tipped in flight.
if it's too big it can have damage when it's squished down.

[ChrisG]

It is very hard to lap a mold but I don't think it is the problem. You are using less MP300 then a 296 load so you are still too slow. I don't know if a highly compressed load of MP300 can reach what is needed. You really need at least 1300 fps. You are shooting Unique velocities.
Thank you for your advice. Alliant doesn't list a heavy hard cast boolit. I am extrapolating a load from their 300 grain jacketed data, hence why I started so low. The other problem may be that the barrel is only 4" so Idk even with 296 if it would reach the desired velocity. Recoil was getting pretty stout even though there were no overpressure signs. Brass still ejected easily. No Cratering on primers and the primers were flat but not mashed. I will continue to bump up the load .5 grains at a time. Currently, it isn't really compressing the load but It is getting there. I know some powders tolerate compression while others don't at all. That's why I am being cautious.

[ChrisG]

are they bigger than your barrel/size die/throats?
if so they are coming out of it round.

you might be damaging the boolit somewhere in the process.
it doesn't have to be O.O.O. to be tipped in flight.
if it's too big it can have damage when it's squished down.

The lands would be round yes but anything that didn't touch the sizer would still be oblong i.e. the nose, the grease grooves etc. There didn't appear to be any damage to the bullet that I could see when I recovered a couple. I don't know. They are size .431 to the throats of the cylinder and the groove diameter is .430.

[44man]

Short barrels can never reach stability. It is said twist never changes but if velocity can't be reached, spin is off. Beating a dead horse does not make him more dead.
NOW the problem is here. Short barrel the MP 300 can't find or 296 either . You have a Bullseye barrel or Unique that brings in other problems.

[ChrisG]

I just ran across this article: http://www.lasc.us/fryxell44overweight.htm. He is shooting a 350 grain LBT boolit from a SBH. Same twist as my gun 1:20". Barrel length doesn't matter as far as I can see because he is only getting 1166 fps out of it and makes no mention of stability issues. He does have stability problems when he moves up to a 365 grain boolit. But he is shooting a longer boolit at the same speed with about the same RPM as I am getting 41,400rpm. He mentions that it doesn't stabilize in a Marlin 1894 with a 1:38" twist. This seems very confusing as my gun is throwing a lighter, shorter boolit at the same speed with the same RPM and I am getting slight keyholes. I may just have a bum mold and have to get a new one. I am thinking of getting mounatin molds to cut me a 295 grain mold of my own design. In the meantime, I am going to buy some 300 grain commercially cast boolits and see if they have the same problem. I appreciate everyones help.

[44man]

I am right at the border with a 330 gr in the .44. I don't know why it still shoots but heavier will not.
But I think different about boolit length and think drive to twist is more important then overall length. 350 and up gets way too long. My boolit is at 47,376 rpms.
NOTHING will stabilize in a 1 in 38" Marlin until you get to a RB. A 310 is at 26,526 if you get to 1400 fps.
I still think it is the portion of the boolit in contact to the bore and not how long. It has worked for me. Greenhill and stupid formulas SUCK. I have piles of them and all are wrong.

[ChrisG]

168812
Here is what the holes from the1150fps loads look like. As you can see, the hole punched by the meplat is slightly off center. The bullet smear is uneven around the hole. I'm thinking this might be more indicative of bullet imbalance and wobble than lack of stability. Idk though.

[Cowboy_Dan]

Are you positive that the boolit is not entering the barrel at a slight angle and travleling stably at that angle to the target? Not that I have any idea of how to test for that, but someone on here might. This has been a sudden idea I had reading through this thread and reflecting that most of my round nose loads appear to enter targets at a slight angle regardlesss of size for caliber.

[ChrisG]

Are you positive that the boolit is not entering the barrel at a slight angle and travleling stably at that angle to the target? Not that I have any idea of how to test for that, but someone on here might. This has been a sudden idea I had reading through this thread and reflecting that most of my round nose loads appear to enter targets at a slight angle regardlesss of size for caliber.

Hi Cowboy Dan,

I was considering it and some of the recovered boolits seem to have slightly longer grooves on one side (<1/16") than the other, but I chocked this up to the boolit being out of round. When I shoot Jacketed boolits from the gun, they seem to hit perfectly dead on, if it were misaligned, I would think I would have the same problem with them as well. Also, I shoot a 240 grain LRN cast from a lee mold and it seems to hit pretty dead on too, (although this is hard to prove as RN boolits don't tend to punch nice clean holes to begin with). If it is entering at an angle, is it likely because the cylinder alignment is out of spec? I was a little concerned about that to begin with and I don't own a range rod to check it so I looked down the barrel with a light behind the cylinder. It looked like it might be just a touch off but its really hard to tell. So I ran a square end brass rod down to see if it caught on the edge of the throat. It didn't so I didn't think I had a problem.

Also, if I have to send it back to Ruger, they're going to want to know what I shot through it to prove that it isn't hitting straight. They frown on handloads so I would have to go buy a couple different boxes of factory ammo and hope that they replicate the problem. I hate to do that. I just love my handloads. They are like a warm fuzzy blanket.

Thanks for the input

[44man]

Are you positive that the boolit is not entering the barrel at a slight angle and travleling stably at that angle to the target? Not that I have any idea of how to test for that, but someone on here might. This has been a sudden idea I had reading through this thread and reflecting that most of my round nose loads appear to enter targets at a slight angle regardlesss of size for caliber.
Good point but if there is some play in the cylinder, the ogive can pull it.
Then a hard lube might not leave a boolit and throw it out of balance. A chunk of lube on one side is as bad as casting air holes.
Long ago when shooting IHMSA and watching thousands of bullets/boolits through a spotting scope, I would see over spun 240 gr from the S&W rotate around the flight path but the guns all could do 1/2" at 50 meters with opens. POI would change only from the point of rotation it hit, very small amount. Ruger did not display this at all but stepping to a 250 or 255 in the S&W also stopped it. Boolits ran true.
S&W has a 1 in 18-3/4" rate and is better for heavy boolits but parts inertia and damage from recoil limits boolit weight. What I learned is a little over spin is just fine. But slowing the 240 would work too. Needed ram slammers though.
The Ruger 1 in 20" can handle from 240 and up quite a bit as long as you keep velocity at what a boolit needs. True, you can't exceed pressures so a heavy boolit will still be slower but if it is enough, stability is there. Working loads has showed groups tighten as powder went up and then start to open again so I step back to the best. Now going to the 400 gr in the .44 had sideways impacts because the boolits ran out of steam. Same with stupid 700 gr in the .500 S&W, doesn't work! The 310 Lee is one of the very best in a Ruger. But idle speed is not right.
I don't like light speed but just stability. Push too fast and groups open.
Funny the S&W still held groups with too fast and the grip configuration did the gun in at IHMSA. I could shoot a 1/2" group, set the gun down, pick it up and still shoot a 1/2" group but it would be 10" from the first. Poke the center from the first 5 chickens and miss the next 5. All S&W 29's went down the road and I had 5 or 6 including the long IHMSA gun with the funny front sights that never worked. Ruger kept clicking.

[ChrisG]

Good point but if there is some play in the cylinder, the ogive can pull it.
Then a hard lube might not leave a boolit and throw it out of balance. A chunk of lube on one side is as bad as casting air holes.
Long ago when shooting IHMSA and watching thousands of bullets/boolits through a spotting scope, I would see over spun 240 gr from the S&W rotate around the flight path but the guns all could do 1/2" at 50 meters with opens. POI would change only from the point of rotation it hit, very small amount. Ruger did not display this at all but stepping to a 250 or 255 in the S&W also stopped it. Boolits ran true.
S&W has a 1 in 18-3/4" rate and is better for heavy boolits but parts inertia and damage from recoil limits boolit weight. What I learned is a little over spin is just fine. But slowing the 240 would work too. Needed ram slammers though.
The Ruger 1 in 20" can handle from 240 and up quite a bit as long as you keep velocity at what a boolit needs. True, you can't exceed pressures so a heavy boolit will still be slower but if it is enough, stability is there. Working loads has showed groups tighten as powder went up and then start to open again so I step back to the best. Now going to the 400 gr in the .44 had sideways impacts because the boolits ran out of steam. Same with stupid 700 gr in the .500 S&W, doesn't work! The 310 Lee is one of the very best in a Ruger. But idle speed is not right.
I don't like light speed but just stability. Push too fast and groups open.
Funny the S&W still held groups with too fast and the grip configuration did the gun in at IHMSA. I could shoot a 1/2" group, set the gun down, pick it up and still shoot a 1/2" group but it would be 10" from the first. Poke the center from the first 5 chickens and miss the next 5. All S&W 29's went down the road and I had 5 or 6 including the long IHMSA gun with the funny front sights that never worked. Ruger kept clicking.

There is some play in the cylinder. I can manually turn it enough to fully align it. But as I look at other peoples targets online, I am thinking that the hole punched by the meplat being slightly off center may just be normal. I need to load up about 50 rounds and see if they all do that. If they are consistently hitting like that and grouping well, I am not going to worry about it. I just saw a pic online of a target shot by a rossi puma M92 .454 casull at 50 yards with 300 grain LFN and his holes were slightly off center too, even though his bullet was moving nearly 2000 fps. It may just be the nature of cast bullets. Unless I want to turn them all on a lathe, I have a feeling that this is pretty par for the course and I am just nit picking little stuff that really shouldn't bother me. I will load up 50 and see how it goes.

[runfiverun]

it could be the cardboard your putting the holes in too it has little waves inside it.
they could easily be flexing at the unsupported points making it appear as if the holes are a little crooked.
I'd just get the holes as close together as possible and not worry about it.

[popper]

Agree with R5R - can't really tell much from the posted target. Your first post said tumbling but you've changed to load. Try comparing targets out to max range you can shoot, see where the (real - if any) problem occurs. Target is 40SW 165gr TCPB @ 15 yds (~950 fps) - holes look the same at 7 & 25. What causes it? Who knows. Target not perpendicular to path, nose starts to mushroom, boolit wobble? Rifle at HV does the same thing. Jacketed SP make nice round holes.168855

[ChrisG]

Agree with R5R - can't really tell much from the posted target. Your first post said tumbling but you've changed to load. Try comparing targets out to max range you can shoot, see where the (real - if any) problem occurs. Target is 40SW 165gr TCPB @ 15 yds (~950 fps) - holes look the same at 7 & 25. What causes it? Who knows. Target not perpendicular to path, nose starts to mushroom, boolit wobble? Rifle at HV does the same thing. Jacketed SP make nice round holes.168855

yeah my first loads were legitimately tumbling. 1 out of 5 would hit almost sideways. 2 or 3 out of 5 would be seriously canted. I bumped the load up to 1100-1150fps and it seems to have evened out, but I haven't fired enough of them to see if it truly solved the problem. Also, everytime I change loads, my point of impact changes and so it takes me a round or two to find it again. So I just need to load up 50 of these and see if they all hit like that and if I get any further stability issues. Thanks for the post. I may just be expecting too much from my cast bullets. The wobble I am experiencing at higher speed may have been enough to tip a bullet that was not spinning as fast due to the initial loadings I had.

[44man]

Only comment I can add, cast can and will shoot as good as any bullet. Not as easy as buying but they work.

[ChrisG]

169126

169123

These are some of the targets I shot today. As you can see still have some wobble. 25 yards. 22 grains 300mp 1205fps.

[williamwaco]

it could be the cardboard your putting the holes in too it has little waves inside it.
they could easily be flexing at the unsupported points making it appear as if the holes are a little crooked.
I'd just get the holes as close together as possible and not worry about it.


+1 on that.

[44man]

Shooting farther can tell more. I start at 50 and most shooting after sight settings is at 100.
Cardboard CAN tilt the hole as can loose paper but other then that, I don't know why a hole is not round since even with a better then 2' pattern I had round holes. Meplat and ogive shape??? keith made his boolit shape to cut round holes in paper but a meplat for game.169164 My 200 yard drop test showed pretty round holes. Then 2 shots on a cardboard chicken at 200 meters still look good. 169165
With a little cylinder play the Lee 310 is hard to get an off center start, it is a darn good boolit. What happens if you do, I don't profess to know other then out of balance and maybe lube alone.
If you think a lube will not do funny things, look here. Same boolit at 50 yards, just a lube change. 169166 LBT hard blue on the left and Felix on the right. Yet all holes are round.
I was crazy when I could see and thought 500 meters was revolver country and I did out shoot some of my rifles. 500 meters is 547 yards. See what happens at range, might be seeing something not important.
Working loads is more important so if groups make you happy, go with it. Most bad results are from a small thing you ignore. My problems were with jacketed and after solving, it works with cast exactly the same. My cast are all loaded with jacketed tools.
The hours I spent staring at rounds and feeling my loading and shooting might make a few books.
I have had a good thing, load a few and test without 100 miles to a range or pay for a test. That will shorten the curve. Have my own range and even in Ohio, it was minutes to a farm. Many of you need to load and get a weekend to go shoot. You want to shoot more so you load 200 rounds the same. It is called "HOPE."