High velocity with usable accuracy? You decide!

[303Guy]

I came accross a record in which I wrote .69 MOA at 200 metres. I don't remember that but I do know the rifle was scary accurate and flat shooting out to 160m. By flat shooting I mean the bullet did not rise or fall more than 40mm from the line of sight out to that range. This rifle had a rust damaged bore and an oversized chamber, possibly reamed to remove rust pits.

I do think Lil'Gun will perform well in other cartridges with the same scaled up geometry but I'm not sure how to do the scaling up.

There is another way to seat a boolit in an unsized neck when the fit is quite close but not close enough to hold the boolit in place.



This requires a powder charge that fills the case right up to or into the neck and a cardboard wad that actually seals the neck. Then a little blob of a stiff lube like my 'waxy-lube'. The trick is to warm the boolit then set it on the blob of lube and it melts itself into place. That trick did work but the clearance was too large to give a firm enough grip.

[DrB]

So the benefit is the pre expanded neck holds concentricity to the neck of the chamber, the paper patch holds the bullet concentric to the case neck, and the lube glues the bullet in place and gives consistent release of the bullet? Sounds like a benchrester trick.

So .69 moa, 200 yd was after (about a 1.5" group), what was before?

How did you form the paper cup, and from what? Guess you had to hunt the thickness to give you the right concentricity?

[dverna]

3600+ fps is hard to believe with a cast "range scrap" bullet. Did you verify the chronograph is reading correctly? If so, very impressive.

Like Larry, I see the "wee" calibers as needing a higher level of accuracy than minute of an orange. But, you have made an excellent start, and load/bullet development may provide interesting results.

I am too inept to even attempt cast bullets in the .22 CF's - so I envy your ability.

Great work sir!

Don

[nanuk]

what is the RPM of that boolit?

[NHlever]

Some of us have gotten pretty spoiled with the good components that are available today pretty much on demand. Production barrels are much better these days too generally (or they can be if the manufacturer wantss them to be). I can remember in the early 60's getting pretty excited about a MOA group at 100, or 170 yards out of the .222's, and 22-243's we were shooting. We didn't have a longer range, but we were shooting woodchucks at longer ranges than that, perhaps to nearly 400 yards with the 22-243. To even think about those velocities from cast boollts is as exciting as the smaller groups were back then. Keep up the good work Dan.

[Bullshop]

-----what is the RPM of that boolit?-----

I dont know. I forgot how to figure it. Lets see 3650 fps X 12 = 43800 inches divided by the rate of twist 14" = 3128 = rps x 60 = 187714 rpm.
Does that sound right?

NHlever
That is exactly what I am thinking. If I in my available time can not do it someone else will pick up the ball and run with it. Once the velocity myth has been done away with its time to figure out what the truth is.
I have lots of ideas to try to improve on accuracy and feel confident I will get much better than the pics posted. That was just a starting point.
Yesterday I was able to improve the grouping a bit by going back to the Win 680 powder.
When I first used it I went from H-110 then to W 680 then H4227 thinking I was going progressively slower.
Yesterday I checked a burn rate chart ans see that the W 680 is quite some slower than the H 4227. I had previously had quit at 18gn W 680 for 3441 av, fps but went up to 18.5gn of the faster H 4227 for 3650 fps.
For this reason I went back and tried 18.5gn of the W 680 and it went right up to the velocity of the H 4227 load at 3650 but was giving slightly better average accuracy.
Actually accuracy was quite good accept for a flyer now and then. For instance out of ten shots in a group 7 or 8 might be in 1.5" while the other couple would go 3 to 4 inch.
This shows potential and that I have to figure out the flyers.
To be honest I have not put any effort into weighing boolits or powder charges. The boolits are used as they come without sorting of any kind other than to cull anything I see with a defect when I am size/lubing them. I may go there in the end but want to refine other things first.
What I see with these high intensity loads is exactly what I see in working up loads of the same intensity with jacketed bullets. Small changes in powder charge can make quite a difference in finding the best accuracy for that powder same same.
I did find a point at which I was beginning to get leading. That point was at the same point that primer pockets began to streach. The same pressure with jacketed bullets will also produce metal fouling so again same same.
The leading I get was in the breach end of the barrel and comes out on a patch as small flakes. Still one wet patch followed by a few strokes with a brush and then a couple dry patches cleaned it all up and had it ready to shoot again.
BTw the velocity that produced this condition was right at 3700 fps + or - and the pressure was too much for any bullet/or boolit.
This is a velocity area reserved for 22/250 and the likes but not for a 221 fireball, or is it?
I think we have all been selling the potential of boolits short, at least the velocity potential. I think within the limits of the cartridge that a boolit has the potential for higher velocity than its bullet counter part of equal weight and equal pressure.
Accuracy is then the issue. No doubt at least at this point of acquired collective knowledge that the bullets is more accurate at absolute top end. When its all said and done what will be found to be the % of accuracy lost by using a boolit rather than a bullet for such loads. My part in it is to make that the smallest number I possibly can.
Yea I am rambling

[303Guy]

Bullshop Have you thought of trying Lil'Gun? I suspect it does start to pressure spike at higher levels in a bottle neck case but otherwise it produces higher velocity at lower pressure. Just a thought.

[Bullshop]

Not yet. I have some and may try at some point but I left that burn rate behind when I left H-110. I felt since I had plenty of room left in the case the H110/Lil-Gun area of burn rate wound not prove optimum.
The W-680 seems about optimum for pressure to case volume. At 100 % I am getting the top safe loads. Slightly compressing is over the top.
I did try an even slower powder yesterday in Norma #200. With the Norma powder I passed optimum for burn rate because a slightly compresses load would only produce 3500 fps. It was looking pretty good for average accuracy but since I have had a taste of 3600+ the lowered velocity doesn't seem to achieve the same climax so to speak.

[303Guy]

I think I agree with your Lil'Gun surmise. You might be forced to settle for 3500fps and better accuracy but that would be a last resort, right? Did you mension the twist rate? I'm getting real interested heare because I have this long 22lr barrel that I'm itching to build into a 303-220 Swift. Such a rifle would be quite pointless if I can't get high velocity and good accuracy with it but I might be a bit ambitious with the case size. Perhaps it would be cleverer to build on a 30-30 case. I would then keep a long neck and use it for an under boolit wad. Aah! That would be a 22 Savage with a smaller bore!

[303Guy]

So .69 moa, 200 yd was after (about a 1.5" group), what was before?

The rifle didn't do too well with conventional loading but once I moved to Lil'Gun and higher pressures, the accuracy improved. Unfortunately I live in a windy place so getting groups at the range was difficult.

Apart from my 22-303 or 22/30-30 project, I might just try plain cast with those paper cups in the hornet. I form the cups with a little tool I made.



Here's the tool I made for cutting the paper strips.

[303Guy]

3600+ fps is hard to believe with a cast "range scrap" bullet.

I'm interested in this because I have this long 22lr barrel with a 1-in-16 twist .... mmmm

[Bullshop]

Your 22/30/30 would be closer to the 219 Zipper. I think maybe if I were to use the 30/30 case at 22 cal I might consider the 219 Donaldson Wasp.
It will get all the speed possible from a 30/30 case but have a better adjusted powder volume.
BTW the 221 I have been using is a 1/14" twist
I have a BRNO 110 in 222 also with a 1/14" twist. I plan to give it a whirl next. The larger case will allow a slower powder and may get the same velocity at a lower pressure.
I used to think that the lower pressure was important to best accuracy for boolits but now I am not so sure. I have been wondering in this if there is a window of pressure at the mid range that should be avoided. What I mean is that for the longest time we thought that we were limited to very low pressure for boolits.
We would work up loads that were nicely accurate then at some point leaving moderate pressure groups would open so we stopped and thought thats it right there that top pressure for accuracy. But is it? If we go beyond that moderate pressure window that yields poor accuracy right on up to NORMAL industry pressure will we again find another accuracy slot at the top end? I have to wounder.
Is something going on with the higher pressure actually making the alloy act harder?
The higher pressure at the base has to mean there is also higher pressure on the sides, the bearing portion of the boolit which might make the alloy act harder than it is.
I dont know I am thinking out loud but I have to wounder.
We have always tried to stay below the pressure that would exceed the shear strength of the alloy. That pressure at below may make an alloy act in one way but if we exceed it to a point that the alloy becomes more elastic can it then regain the gas seal and behave normally again. I dont know I dont have the answers. What I do know is that this experiance is making me have to look at what I thought to be true differently.
Also that I have a lot of shooting to do to find out.
The range scrap that I made the first batch of boolits from was brought in to me by a customer. He had picked up a bunch of boolits at the Delta range and melted them into ingots. When I have been to that range what is see looks to be about 50/50 of commercial cast and jacketed. I would guess the commercial cast to be very hard.
The batch of boolit I made from that alloy are not all that hard. I intend to make up a batch from my favorite alloy 6ww/1 mono and quench harden them.
That alloy will cast very nice clean boolits that will be quite hard when quenched.
Like I said lots of shooting to be done.
I just got done match prepping some cases and am on my way to the range to try again.

[WyomingWhitetail]

bullshop beat me too it but i was going to say a 22/30-30 is a 219 zipper. I have heard of people making full length 22/30-30 and ackley improving them. You have some very interesting ideals bullshop and just completing my second year in school for mechanical engineering you have me asking some serious questions to myself. Might have to dig out some of my books and do some reading. You have me wondering what i can do with my 219 zipper.

[DrB]

The rifle didn't do too well with conventional loading but once I moved to Lil'Gun and higher pressures, the accuracy improved. Unfortunately I live in a windy place so getting groups at the range was difficult.

Clever tooling set up, 303Guy. Thanks for sharing. What's the process RE forming the cup? You cut the strips with your shear tool, lay the strips in the holder, press a bullet in past the cylindrical section and then back out? How do you get the paper strips to stay in place? You seat into the unsized hornet case neck through your paper strip holding tool? Never mind, I get it now that I see the case holder/brass under your tool.

+1 on your Lil Gun experience RE pressures... Though I have no experience with Lil Gun in a bottle necked cartridge other than a K-hornet. In K-hornet, I've gotten >3000 fps with a 45 grain all-copper bullet + compressed load, pistol primers (soft) and no flattening at all of the primer. Seems to suggest the pressure profile may be benevolent for a lead bullet. Of course the primer indications are a SWAG, and are from the case end of the equation and not the bullet base, which is what matters as far as abuse the bullet sees.

With 35 grainers I've gotten >3400 fps, also with no pressure signs. One load variation at 3350 fps showed a Standard Deviation =18 fps. I thought that was pretty good, though it seems like I should be able to improve from the data (seems bimodal? About half of the data points were identical, but then I don't know what the discretization is on my chrony at ~3000fps, so that lack of variation may not mean anything.

[DrB]

btw -- anyone here or passing through that has a NOE 107 mold, I'd like to get a sample of a few dozen unsized boolits quenched to ~23 BHN to try with a K-Hornet load around 3300 fps. I'd be willing to offset your cost (shipping + a buck or two) if you want to PM me.

I think it would be interesting to see if my K-hornet will go to ~3300 fps without heavy leading/bad accuracy using these NOE 107 bullets substituted for jacketed in my Lil Gun load. If we can get this going I'll post results here.

[Larry Gibson]

Actually accuracy was quite good accept for a flyer now and then. For instance out of ten shots in a group 7 or 8 might be in 1.5" while the other couple would go 3 to 4 inch.
This shows potential and that I have to figure out the flyers.

Bullshop

Those flyers are telling you something. Probably 187714 rpm. That's why I suggest shooting at 200 yards to see if the group there is linear compared to the 100 yards groups. If the 1.5" 7-8 shots run 3 - 4" at 200 then you've just got to figure out why the 2-3 flyers were going south. If the 7-8 good shots show a non linear group expansion at 200 yards then the RPM is the problem, not the cause but the problem.

Larry Gibson

[303Guy]

How do you get the paper strips to stay in place?

I push the strips trough to the case with a rod, hold the rod down then lift the little tool thing of then remove the rod and tool. The bullet gets seated and the excess strips get cut off with an invered 223 case over the bullet. Soon to be boolit!

I'm gonna have to get this hornet out of hiding and start having some fun with it again - this time with real boolits!

[KennethF]

Bullshop, I would like to offer a suggestion that may help you to improve your shot groups while doing your load development for this project you are working on here. Maybe you are already aware of and using these accuracy improving methods, if so this may be useful to others following this thread. In your post #46 you state that when fireing 10 shot groups, you are able to get 8 shots in 1.5" and 2 shots will be flyers causing the growp to become 4" or 5" groups. So all you need to do is eliminate the flyers.

In Harvey Donaldsons' book, "Yours Truly Harvey Donaldson", in the chapter called "Finding The Cause For Flyers", Harvey writes that many times neck wall thickness variations can be the cause of flyers, do you turn the outside of your case necks to uniform them? The next suggestion he offers is if you shoot a group of ten and you get 2 flyers, segregate the two cases that caused the flyers and shoot a group of 8 using the cases that produced the thightest portion of the previously shot group of 10 and see if that elimates the flyers. Harvey also says, any number of things, seen and unseen can be wrong with the bullet to cause a flyer, as well as an improper barrel crown.

To eliminate those cases that produce the flyers may eliminate the flyers if all else is equal.

Good luck.

Ken

[DrB]

Bullshop et al -- a range report is posted at the link below with my results using Bullshop's NOE 107 bullets and Lotak lube.

http://www.castboolits.gunloads.com/...14#post1352414

[Bullshop]

Ken
Thanks for reminding me. I have that book and have always been an admirer of Mr Donaldson. I have learned much from the book of his articles but sometimes forget to put it into practice.