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Hi- Just started working up loads in a custom 98 Mauser in 338-06 AI using Varget, CCI LR primers, and the 200 gr Hornady bullet. Started with Winchester 30-06 brass and fireformed with 44 gr Varget and the bullet seated firmly into the rifling (same bullets). Bullets are now seated off the rifling by ~0.015" or so and I used a very slight crimp into the forward side of the bullet channelure (Redding dies). This leaves about 1/8" or so between the top of the powder and the base of the bullet (the bullet does not enter the case past the bottom of the neck). I'm getting flat primers at 55 gr of powder. The book lists loads for the regular 338-06 with this bullet and powder in the range of 43.5 gr to 57.3 gr. With the improved case, I don't think 55 gr of powder is an excessive load - I should still have some room to run here. The primers are not totally squashed, but the flattening is noticeable on 7 of the 10 rounds fired. Brass length is 2.465" to 2.480" after firing. The longest cases are not those with the flat primers, so I think the case length is ok. I'm assuming that the case length is the same as the standard 30-06 trim length... Any ideas on what to check for? My chrono is not running at the moment, so I don't have velocity figures yet. Maybe later this week. This is a new rifle I just put together, so I know the headspace is right on. Chambering and extraction are easy. Maybe these primers are not tough enough? I've been using CCI primers exclusively for years with no problems, though. Since this is 30-06 brass expanded to 338 caliber, I don't think I am having a problem with thick necks. Any ideas would be great. thanks, maxman | ||
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CCI primers are pretty hard, and flattening usually means high pressure. A good indicator is how many loads you get before primer pockets loosen and primers start going in easier. If that happens in fewer than five reloads, pressure is too high. Wildcats vary even more than standard cartridges, so you can't put too much stock in published data. It just gives you an idea of where to start. Varget often prefers CCI benchrest primers. | |||
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MaxMan, I load for and shoot a .35-06 (.35 Whelen) and I think that headspace is your likely culprit. Test case length by trying to seat a bullet in a fired case with your fingers. If it's too long, the mouth will grab the bullet. If OK, the bullet will fall in. One problem I ran into when forming cases is that the neck expansion step wants to push the shoulder back a tad. This means that if you simply take .30-06 cases and run them through your F/L die, the shoulder has been slightly moved back and thus modified headspace. One fireforming may or may not fix this, and stretching will occur regardless. The problem may not show up with the light (44 grain) load, since the case isn't getting shoved back around the primer. I would suggest bumping the the 30-06 neck to .35 (I use .375 for my .35), and then adjust your sizing die to just allow the bolt to close. This forms a secondary shoulder in the correct place until you get it formed. Failure to keep this shoulder in the right place will cause premature head separations. Good luck, Ed [ 08-25-2003, 23:59: Message edited by: eshell ] | |||
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I agree with eshell. Likely a headspace issue. I have a 338 Hawk (close to a 338-06AI). I have used both 35 Whelen and 30-06 to form brass. I always neck up to 35 and then use the 338 false shoulder for a snug fit. It takes a pretty stout load to fire form - sometimes the shoulder is not sharp until the second firing. I get 60 grains of Varget with a CCI BR2 and 225 Nosler Partiton in Remington brass with no pressure signs. I backed off to 59 grains and get a 1" group at 2771 fps with a SD of 8. I started at 54 grains and worked up over a chrony. My fire forming load is 54 grains of 748 with a 200 Hornady. Shots .6" groups but only 2530 fps. It could be the excessive neck length causing high pressure. I don't know what the trim to length for the AI. The Hawk is 2.465 RL 15 and H414 have worked well for me, but can't get enough H414 in the case to push the 225 or the 200 NBT(longer bullet) . My best loads are RL15 200 NBT at 2850fps H414 210 NPT at 2860 fps Varget 225 at 2770 fps I have ssen other claim these types of velocity with a standard 338-06. Maybe I have a slow barrel or maybe I'm a little conservative. None of these appear to be high pressure loads. I have yet to loosen a primer pocket. Never had a hard bolt lift. Have used the 210 NPT load with great results on a Mule Deer, an Antelope and a Whitetail (20 yds to 300 yds) I just tried the 225 Accubond ( a verrry lonnng bullet) with mixed results. Getting lower velocity with the same load as the 225 partition. Only one experiment and that with Varget. Think I will stick with the three I have that work, good luck | |||
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Thanks for the tips. These cases all *appeared* to form well initially. This is my first wildcat round, so I might be wrong.... The shoulders are nice and sharp, but I did get pending head separation signs with two cases during fireforming. At the time, I wasn't sure why. These signs appeared on the few once-fired cases I had around. All the new brass seemed to form up with no problem. I did verify the chamber itself is right on with the 338-06 AI headspace go/no-go gauges, so the problem must be in my technique. Here is my question then: When fireforming an AI case using a bullet seated into the lands, should the case/chamber be lightly oiled or really dry? I was thinking it should be oiled to allow the case head to slide back to the bolt face and allow the shoulder to push out forwards, but I could be wrong. I've heard conflicting advice on this one. I wanted to form all brass from 35 Whelen cases, but could not find any when I needed them. Running them thru the sizing die would produce the needed false shoulder right where it should be for proper headspacing with one operation. I opted to run 30-06 cases thru the sizing die to expand the necks and then partially seated a bullet. Camming the bolt shut jammed the bullet into the rifling and finished seating the bullet, which should have held things in place for forming - I think... Can a .358" expander plug be swapped into my 338-06 sizing die for the first expansion? I am not sure if there is room inside of the die, or if I will need to scrounge up a 35 Whelen sizer die in order to do the initial forming. I didn't want to buy a die for a rifle I will never own. I could order 35 Whelen brass from somewhere, but that will seriously hamper my development here. Using 30-06 cases will be easier for me. Of course, I could save on bullets if I had brass with a false shoulder, as I could fireform with an inert filler of some sort. thanks for any further tips.....maxman | |||
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quote:It's tough to 'see' a difference, since the dimension is taken from the center of the shoulder and it is only a few thousandths short. quote:This further convinces me you are inadvertantly inducing excessive headspace. Any time you get a separation with one or two firings (and maybe even at all, there is a dimensional difference the brass cannot stretch to meet. quote:Agreed, it is easy to allow the headspace to be increased while forming these particular cartridges. quote:My personal opinion is that the cartridge and chamber should be dry at all times. I know there are differences of opinion regarding this, but anytime I've seen reference to lubricating the case was with some squib load under wax or cream of wheat or some other foreign matter best kept out of your bore. To me, bolt thrust is increased dramatically for no gain, since the case WILL move if it has to, lube or no. JMHO. Further, another one of my damn personal opinions is that seating the bullet into the lands is useless in controlling headspace and I would really try necking up for the secondary shoulder as we had suggested above. Some use this method, but it has never worked for me. quote:I agree that this would have been the best way to start. quote:This would have been fine, but your shoulder isn't able to stay where it is and still support the neck under the pressure of forming the new neck. quote:I think it would have, were it not for the firing pin seating it a little deeper (perhaps the same distance as the headspace error) upon firing. The firing pin drives it forward another few thousandths and moves the case head off the bolt face enough to stretch your brass. To resist the forces attempting to drive your case forward, the bullet must be seated quite tightly, maybe even too tightly to chamber if too long. quote:If you are using standard RCBS or standard Redding F/L dies, yes, you should not have a problem swapping expander. There is definitely room in your die for a larger expander "ball". The only thing in your die tighter than a .35 Whelen (or a .375 Whelen, for that matter) is the neck, which is nowhere near the expander. All you need is the expander ball, with RCBS it is often available as a spare part at your well-stocked sporting goods store. RCBS makes a service parts kit with lock rings, seating & decapping stems, expanders, decapping pins, etc.. quote:If you are able to get your hands on a .35 expander, I don't see any need to get anything except 30-06 brass for your project. An idea, if you want to do it "quick and dirty", is that a pistol die for .38/.357/9mm would do the job, provided you limit penetration of the case neck. A .35Rem die would also serve, if you couldn't borrow the expander from it to use in the correct die. Even using a .35 expander in your .338-06 die will require that you do not enter the neck portion of the die with your cases. quote:I'd stay away from fillers, myself, until Shooter's Choice starts making an oatmeal solvent. As little actual forming that you are doing, methinks that if you bump the necks, then size for a tight fit in the rifle, you can likely simply start working up your hunting loads. Effectively, it would be like shooting regular 30-06 ammo in a 30-06 Ackley chamber. One final caution: The cases you are using are damaged. Sad, but true. Due to stretch just above the web, your safety margin is diminished. If you have already suffered a few pending or partial separations, many of your other cases are close to the same point of failure. Got shooting glasses? Hope this helps. Good Luck, Ed [ 08-26-2003, 22:19: Message edited by: eshell ] | |||
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Thanks Ed. I do load 357 Mag, and thought about using those dies to expand the 30-06 necks, but wasn't sure if that would work. I have Lee carbide dies in all my pistol calibers (they are great by the way!) The expander ball does not match the threads in the Redding die. So, I could just use the 357 die as is, limiting the case entry into the die to just the neck?? That would be slick and cheap! I'll pick up a new lot of brass and start over. I was afraid that these cases were in trouble. I couldn't detect any bright rings outside or any thinning inside with a bent wire, but it could be waiting for any moment to actually fail. Eye and ear protection all the time! maxman | |||
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When you are fireforming an improved case do not use a mild load. If you do, you will end up with cases which are short in headspace. This is what you have done. The case should headspace adequately on the juncture of neck and shoulder if the barrel is chambered properly. Instead of 44 of Varget to fireform, 54 would be more like it. Regards, Bill. | |||
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quote:Yes, all you want to do is bump the neck enough to produce a difference for your cartridge to headspace on. I agree with Bill above, I never use reduced loads to fireform either. I make .35 Whelens,.280 Rems and .30-06 AI's from '06 brass, and 6.5-300's from .300 Weatherby brass and always use the starting load I would propose to work up from. To me, whether your fireforming loads are full power or not, it is still important to have the correct headspace dimensions to begin with. I do stand corrected by Bill as well, your initial headspace will be set at the neck/shoulder junction as Bill says, not at the shoulder datum. The shoulder datum is for standard bottleneck cartridges, and yours will also headspace there after the first firing. Incidentally, this is the area most affected by down-pressure of reforming the neck. Regards, Ed | |||
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I like the idea of using the 357 die to neck up. Will try that next time I form brass. Then I don't have to change the expander in my 338 die back and forth. Thanks | |||
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| <eldeguello> |
Please see below..... You probably need a slower powder, like IMR 4320, which has proven about the "ideal" in both the .338/'06 and the .338 Gibbs.... ![[Big Grin]](images/icons/grin.gif){kind=icon} | ||
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You can't tell what is going on without your chronograph. Your velocities may be way up there, even with the 55 gr charge. | |||
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Well, gents, the 357 mag die idea was a bust. There was no way to make it work to expand the neck of a bottleneck cartridge. SO, I bought a set of 35 Whelen dies - which might not be a bad thing to have around anyway Once I ran my new lot of 30-06 brass thru the 35 Whelen die, and then back thru the 338-06 dies, I was able to adjust the false shoulder so the case was an exact/slight crush fit in the chamber. I put 55 gr Varget in these cases and seated one of the Hornadys normally. Everything came out fine. No pressure signs, no shiny ring on the case after firing, a very crisp blown out shoulder, and even pretty good accuracy. Still no chrono data, but that will be coming as I load and test the formed cases. Now to zero the scope! Thanks again for the tips. I was hesitant to buy the 35 Whelen dies, but I can see they are a good investment for me, as I cannot buy 35 Whelen brass locally. Now I can use any 30-06 brass to make new cases (safely). Much easier than depending on mail order for brass. I might even have to build a Whelen at some point now..... maxman | |||
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Glad to hear you've got it worked out! Now for the hunting stories . . . Sorry the .357 dies wouldn't do it, would have been too convenient. Though I'm a long-term .35 Whelen fan (into my 3rd since '74), I say you already have it well covered with your .338-06. Good luck, Ed | |||
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quote:Isn't that always the way, GTC, the fireforming loads outdoing the final product? ![[Roll Eyes]](images/icons/rolleyes.gif){kind=icon} I just shot a bunch of .30-06 AI fireforming loads day-before-yesterday that were just picked from the book only because they matched my inventory. I had a mixed bunch of Nosler 150 BT's and a partial, old can of IMR4350 I wanted to dispose of "properly". I used starting loads listed for the standard .30-06, as you suggest. At 100 yards, bullets were touching. ![[Cool]](images/icons/cool.gif){kind=icon} Probably get 1-1/2" from my matchkings . . . . [ 09-05-2003, 20:17: Message edited by: eshell ] | |||
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