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bjornborud
As I’m getting some ammo ready for my 30 XCB rifle, I’d like to share this contraption, fabricated by Goodsteel: It’s a guided breech seater, made to fit the front and rear rings of a large ring Mauser. The idea is to seat the bullet (we’re talking about the NOE 310-165 XCB bullet) until it fully engraves, i.e. all the way to the gas check.
bjornborud-
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Larry Gibson
I’ve found through extensive testing over many years with a fast 10″ twist .30 cals (.308W, 30-30 and 30-06s) using medium burning powders it is difficult to get any acceptable accuracy over 2000 fps regardless of other changes (lubes, GCs, GC seating, etc.) one might think would work. Appears breach seating is not a magic fix to exceeding the RPM Threshold either.
Further testing with know accurate loads at higher velocity is still warranted. I am looking forward to testing Tim’s Breach seater in my 14″ Palma rifles with a load at 2700 fps where the pressure trace shows the psi required to push the bullet into the bore and rifling. By measuring not only any accuracy difference we can also measure (via the Oehler M43 PBL) the pressure trace to see what effect Breach seating has.
Normally breach seating is done with much softer alloyed bullets shot at much lower velocity and psi’s. My question is; with the really much harder alloy we are using (I use WQ’d #2 alloy with a BHN of 22 – 24) does the pressure exerted on the bullet breach seating it manually really produce less damage/imbalance to the bullet? Answer still alludes us and remains to be found.
Thanks to Tim for his initial excellent test. From that we see that breach seating, like many esoteric things, is not the “magic bullet” to success at higher velocity with cast bullets. Whether it is another of the things we can do that has an accumulative affect leading to some success we do not know yet.
Larry Gibson
keithsharp
What is your method when attaching or crimping on gas checks
Detox,
When I first got into the XCB “project”, I was a (below) average caster and reloader. Gas checking bullets was always done the quickest way: Push the bullet base down on the gas check, then run it down the H&I die in the Lyman 4500, lube & size – done! Then when I started to shoot my XCB rifle, with rather humbling results, I sent some of my bullets to Larry Gibson to see if there was a problem with them. Larry found several problems: Not only were the the bullets sized unevenly, there were also several that had the gas checks crimped on crookedly.After looking at how Larry did his bullet prep, and also the prep of several other experienced shooters over on the CB forum, I now do my sizing, lubing and gas check seating as follows: After weight sorting the bullets into batches I seat the gas checks using the Lyman’s gas check seater. That’s my ONLY use of the Lyman 4500. Then I pan lube; with the Kake Kutter it’s a quick job, melting lube, setting up and cutting loose 100 bullets takes about 15 minutes total. Then I run them through a Lee push-through sizing die, and they are ready to load. Quite a bit extra work, but with the HV shooting requiring smaller tolerances, it’s work I’m willing to do.
darrinwright
Expanman, that’s a great question, and one that has started more arguments than just about any other on certain forums.
Larry Gibson and I have been using White Label’s 2500+ with good results so far, Goodsteel really likes Felix Lube, and yet others make their own lubes (Runfiverun uses his own Moly Lube).
I ‘m shooting my XCB rifle tomorrow, and I have loaded up 80 rounds with the NOE 165 XCB bullet and these lubes: 2500+, Felix, Bullshop’s Lotak and Randyrat’s Tac 1. I’ll be shooting 10 shot groups, cleaning the barrel between lubes. Stay tuned.
I have only seen them in the kits; it’s sometimes a pain since the Alox lube can only be shipped UPS or Fedex (no USPS). Also, a .310 sizer doesn’t exist, so I had Goodsteel hone one for me from a .309. These type sizers are sold by Buckshot on the CB forum; he’ll make you the ones Lee doesn’t carry.
bjornb, Have you tried sizing/crimping nose first. My RCBS allows doing this, but I do not know if the Lyman 4500 will?
Push the unlubed bullet nose first thru sizer using matching nose punch (I use RCBS 165 Sil nose punch). You will have to use sizing stem to finish pushing bullet thru. Some sizing stems are too long and will need to be shortened slightly for removing stem from base of sizer.
Ultimately I feel that taper bumping gas check square is best, but until I make one, the above method works pretty good
Excuse me if I sound like a broken record playing over and over and over.
Today I cast 100 30XCB bullets with linotype alloy (water quenched). 50 from each cavity one at a time. I think that casting one bullet at a time allows better venting for best fillout. All bullets from cavity farthest away weighed 158.7-158.9 grains. Closest cavity bullets weighed slightly less 158.6 -158.8 grains. All bullets were weighed after removing that pesky raised vent line whisker from tip of bullet. NOE has corrected this “whisker problem on bullet tip” with future molds.
I cut all sprues even with base of bullet by adjusting sprue plate snug against top of mold, but still swing closed easily. And by opening sprue plate by hand. Bullets dropped out easily from mold into bucket of water. All bullets are very round with hardly any visible or measurable off set.
I may try Ben’s new T/L lube (60 percent Lee alox, 40 percent Jonhnsons liquid paste wax). Bullets are hand dipped one at a time then allowed to dry on bases. I use wax paper to set wet bullets on.
http://castboolits.gunloads.com/showthread.php?259285-NEW-!-!-T-L-Liquid-Lube
sgt.mike
I may try Ben’s new T/L lube (60 percent Lee alox, 40 percent Jonhnsons liquid paste wax). Bullets are hand dipped one at a time then allowed to dry on bases. I use wax paper to set wet bullets on.
http://castboolits.gunloads.com/showthread.php?259285-NEW-!-!-T-L-Liquid-Lube
Detox if you do try it post the results as I am certain others (as well as myself) will find it interesting,
Might be a good route to go with your objectives.
Mikefrankelliott
Another commerial lube that you guys might want to try is, Javalina Schuetzen Lube. It is 75% commerial Alox and 25% BW. I can get you the contact info, if you like.
The lube that I used BSing the 323471 back in the 90’s, in a 32/40 at 2150 fps is 30% Lithium grease and 70% BW. My smallest group at that time was .43 @ 100. You have to stir it a while to get the Lithium mixed in to the BW but, it stays suspended after that.
For guys that would like to pan lube and not use a cookie cutter to get them out, if you use approx. 2 lb of lube in a 8″ pie pan, it will attain a level that will cover the bands on any bullet.
I melt mine on a elec stove at a setting the barely melts the lube (so as not to burn it), I place the bullets in, let it cool and then put the the pan in the fridge, when it cools the lube will pull away from the pan, you then just push the bullets out using a heavy peice of leather between your thumb and the bullet point. With that, you have no extra lube that will build up on a sizer but, all that makes contact with the lube will be surface lubed.
Frank
I may try Ben’s new T/L lube (60 percent Lee alox, 40 percent Jonhnsons liquid paste wax). Bullets are hand dipped one at a time then allowed to dry on bases. I use wax paper to set wet bullets on.
http://castboolits.gunloads.com/showthread.php?259285-NEW-!-!-T-L-Liquid-Lube
Detox if you do try it post the results as I am certain others (as well as myself) will find it interesting,
Might be a good route to go with your objectives.
MikeI have a few drying (solvent evaporating) on wax paper now. Will compare Ben’s new hand dipping lube against Lyman’s Moly. Maybe tomorrow.
keithsharp
Larry Gibson
darrinwright
sgt.mike
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