Testing the 30XCB

[Love Life]

Probably just a bug somewhere, Larry.

Your last two posts were fantastic. So much proof and hard data and it really helps us.

[Bjornb]

Bjorn, ask Larry if he'd mind if you posted #241 in the "high velocity with cast" thread in CB, it's a lot more topical there as it opens up several good points for discussion which will no doubt derail this thread (in a good way), and I wish his writeup wouldn't get ignored like it's being so far. Neck clearance, bullet shape entering the throat, amount of force =< alloy strength during engraving/swaging through throat (HUGE point), etc. I never had very good results getting HV from fast twists launching the bullet the way Larry does, but slow twists enable him to do more using different techniques. Two different ways of doing things, neither of them is the ONLY way. Larry, please reference my sig line quote by Char-Gar.

Gear

I'll see if I can get a hold of him. I agree that the post should also be over there.

[btroj]

Did a little sizing tonight. It is far easier to get checks to seat square with less effort if I first size in a 311 Lee sizer then lube and run thru a 309. Checks are more uniform and they seem to go on "nicer".

This is beginning to get "fiddely", I hate that. Damn

[GabbyM]

Back a page to the nose first sizing discussion. I have a Saeco 30-150-FN than shoots wonderfully in a couple rifles. Have long suspected much of that consistent accuracy is due to how the bullet fits so nice into my Star .310" size die. I have thought for a few years much could be gained by profiling a size die to fit a specific bullet. To be true to cast boolits. We may want to stop at throating a size die to allow long body boolits to drop in far enough to center up. Carrying it to the Nth degree we'd be swaging a cast slug. Very few of my rifle boolits will easily run through a Star nose first sizer. Any of them would with a custom die.

[btroj]

Went out and shot some today.

I did have something happen that hadn't before- mirage. Bad mirage off the barrel. Temps were 45 to 50 degrees so a barrel warm enough that you don't want to hold it for too long gives horrendous mirage. I can see a need for some sort of a mirage band or something.

I picked bullets a bit more carefully and played with getting checks on more square. Some checks ended up with bad spots on the read corner but that didn't seem to make a huge difference.

Bullets were all water dropped range scrap. No leading, 10 shot groups were all 2 to 3 inches- that size group seems quite easy to get. Velocities ranged from 2300 to 2430 fps. I don't think my rifle will get over 2550 with the 30 Sil and RE19. I have used up to 48 gr, need to see where it maxes out.

At this point I intend to focus more on bullet quality than anything else. I really think that is a huge limiting factor.

I use a .333 bushig in my Redding die, it needs just a slight hint of flair to let bullets seat. I seat long enough to let the throat finish wearing the bullet. Bullet pull is low enough that this requires minimal effort but bullets don't move easily with the fingers.

Best news of all- I found a partial box of Fed 210 match primers! At least a few hundred left so I can do some testing with those too.

[Bjornb]

That's pretty good velocity in your 12 twist rifle! You seem to be where I'm at: starting to pay attention to the very small details that will make a difference. What about making a batch of bullets from some certified alloy? A couple of ingots of Roto Metals Hardball isn't very expensive. That will eliminate any questions about the range scrap make-up.

I'm getting ready to try RL19, the RL22 didn't produce anything spectacular.

Let me know if you want me to send you some of the NOE XCB bullets to try; the last couple batches came out pretty good. I could send you some as-cast and you can lube and size them yourself. Just say the word.

[btroj]

I'm considering it but that could lead to another mould and that takes money from lathe tooling. Damn it, I hate these decisions!

I need to make a big batch of uniform range scrap. Just melt a couple hinder pounds together in 4 potful the. Combine equal amount from each pot in a second melting, voila, 200 pounds of uniform alloy.

I was pretty happy with the results I got from lowly range scrap. Water dropped it is pretty good stuff, I need to heat treat some and see if a few more BHn points makes any difference.

I see what Rick means by using a close fitting punch for sizing. My Lee 309 sizer has a smaller punch and it left some flashing on a few checks. I need a sizer with a more gradual taper I think, or just use the Star with my 313 sizer for seating checks.

[Bjornb]

Sarge,
Superformance sits directly below the 4831s and a couple of places above RL22. The reason I'm looking forward to trying it is that it's a ball powder, same as H414/WW760, which several of us have now had good experience with.

[Eutectic]

Bjornb,
is the Superformance after the RL-22 or is IMR or H 4350 before the Superformance? I cornfused my self. anyways looking forward to another range report.

I would like to see a burning rate chart placement for Superformance if anyone sees one. Hodgdon talks like it only fits special apps which may be their liability clause for that matter.

Eutectic

[Eutectic]

Thanks Bjornb...... Looks like our ships passed during the night!

Eutectic

[HangFireW8]

Larry, I have no insight into your home network or this forum, but I do know there are other possibilities for not getting to this site. Bad DNS entry at your router or ISP, or nanny software on your computers, router or your ISP could all be blocking your access.

[geargnasher]

If Superformance performs the same way LeveRevolution does then it's actual spot on the burn chart is not relevant. LvR is listed with the medium burners yet has a much slower time/pressure curve than the slow burners up through RL22.

Larry Gibson

That's what I was thinking. Depending on what case shape/size it's in and how much mass it's pushing, the actual burn characteristics are more variable than with a "standard", or what's the word, "digressive" powder". I have a few pounds each of Superformance and Lever, but I don't know nearly enough about them to be trying to generate starting data for this wildcat with the limited amount of data to extrapolate. If you have some better-educated ideas than mine I'd be willing to try those powders.

Gear

[geargnasher]

Went out and shot some today.

I did have something happen that hadn't before- mirage. Bad mirage off the barrel. Temps were 45 to 50 degrees so a barrel warm enough that you don't want to hold it for too long gives horrendous mirage. I can see a need for some sort of a mirage band or something.

I picked bullets a bit more carefully and played with getting checks on more square. Some checks ended up with bad spots on the read corner but that didn't seem to make a huge difference.

Bullets were all water dropped range scrap. No leading, 10 shot groups were all 2 to 3 inches- that size group seems quite easy to get. Velocities ranged from 2300 to 2430 fps. I don't think my rifle will get over 2550 with the 30 Sil and RE19. I have used up to 48 gr, need to see where it maxes out.

At this point I intend to focus more on bullet quality than anything else. I really think that is a huge limiting factor.

I use a .333 bushig in my Redding die, it needs just a slight hint of flair to let bullets seat. I seat long enough to let the throat finish wearing the bullet. Bullet pull is low enough that this requires minimal effort but bullets don't move easily with the fingers.

Best news of all- I found a partial box of Fed 210 match primers! At least a few hundred left so I can do some testing with those too.

I still think the bullets aren't starting straight. I don't think it's necessarily your casting quality. I shoot paper patched whatever junk, not weight-sorted, and sometimes not visually perfect, either, at full-on max jacketed velocities and have excellent results. I could be way off, but I'm convinced the 2-3" groups are from the bullets getting crooked or otherwise balance-deformed during the case-throat transition.

More evidence, my last outing using buffer: Groups were just like yours, then add buffer and presto, three touching. Those 2-3" groups weren't due to bad castings, it was bad launch.

So I'd say stop fixating quite so much on your bullets and experiment more with alloy and powder.

Gear

[btroj]

I need to try some RE15 and N540 with the range scrap bullets. I also need to max out case capacity with RE19 and see what that does. The range scrap didn't get wonky at 48 gr of RE19, good for 2425 fps, so there is room to go up.

So damn many variables that it gets difficult to figure out where to go next. I'm sure that over time a pattern will emerge and it will get easier. With winter approaching ( that cold period we get up north of you, sometimes it includes snow) it gets tougher to get good range time. The mirage today was something new and cold weather will only make that worse. I actually wished I had a slight breeze today.

[geargnasher]

Winter, hmm. Oh, right, that white stuff that makes your feet go numb. Yeah.....don't have that here.

I've been thinking more on what to do next range outing, and I think I'm just going to clean the rifle, change lubes, and go back with the first buffered load to see if I can't get that half-inch thing to hang together longer.

If I'm "good" I might even get some loaded tonight and shot tomorrow after work. Let's hope.

Gear

[btroj]

For now I have settled on Felix for lube. May not be the best in some cases but it will never be a bad choice either.

I suppose I should order some buffer and give it a shot, so to speak. Ha, I made a funny.

I need to get some deer ammo loaded, Dad passed his stress today so it looks like we will be going. Probably his last year so it is a big deal. I will miss this.

[geargnasher]

Take your old man hunting if you have to buy factory ammo.

Yes, Felix lube is really never a bad choice, often one of the better ones. Due to slightly less than tropical weather I just got through loading up a fresh box with Felix lube, H414, and buffer. This will be the second go with the LC-69 brass. Hoping to get to the range before dark tomorrow.

Gear

[btroj]

Buy? Factory? Yuck.

We will get out for a few days. He already spoke to the neoghbor about using his 4 wheeler to help drag deer out.

How much 414 are you using? I'm too lazy to go back thru the whole thread and look!

I really need need to see if I can find some RE17 around here, it might be about right. The 15 is a bit fast, 19 is too slow. Now I feel like I'm Goldilocks looking for a powder that is just right.

[runfiverun]

Brad.
I know someone that has the NOE mold, and would be willing to loan it out,, after another casting session.

[geargnasher]

A

Bjorn's post #241, the repost of mine,. It has a test of LvR with the NOE bullet at 2704 fps. That's in the .308W which has just a tudge less case capacity than the 30 XCB. Thus the same load should produce less psi. Suggest a start load of 44 gr. I haven't been able to find any Superformance but am always looking. Will certainly test it when I do.

Larry Gibson

Brain phart. I read that several times but I was thinking Superformance and disregarding .308 data with the Lever powder. Turns out I was mistaken, went to the second powder magazine and what I have is Lever and Hybrid 100V, no Superformance. Maybe I traded it off, did that with several powders lately but can't remember. Tell me this doesn't get worse as I get older.....I'm in freakin' readers now, my opthamologist wasn't lying that all the steroid injections would advance the presbyopia a few years. Can't wait for the predicted early-onset cataracts to form, that'll be even MORE fun to look forward to.

Brad--start at about 42 grains of H414 with a 180-190 ish bullet and work up from there. Heck, make it easy, start at 41, you have a much longer barrel than I do.

Gear