Question on a .308 mold...

[lead-1]

I just slugged the bore and chamber on my Winchester model 70 in .30-06. I took a sized and trimmed case filled with lead and chambered it, then drove a lead bullet down the bore from the muzzle and tapped on it until it felt solid and the bolt was snug on opening and recorded the following measurments.
The area ahead of the case neck and before the rifling (freebore?) was .310, the bore was .308 and the rifling grooves are .302 across the grooves, it is a four groove barrel.
I have bought a brand new LEE C309-160-R two cavity mold, will I have any problems with bullets from this mold being .309 and the slug showing .310, I plan on shooting a bullet harder than just WW with a gas check.

[Wayne Smith]

Bore is the hole drilled in the blank. Groove is the rifling. You are measuring your bore at .302" and your groove at .308" with a throat of 310". I'm not familier with that boolit, but if it is a bore rider it should fit perfectly. If not "Beagle" the mold and you will probably have just the right size.

More importantly, what size is your sizer? If you are seating gc's you are sizing some. Are you giving us the diameter of your sized boolit or your unsized boolit?

[Bret4207]

First off, just because Lee designates the mould as a .309 doesn't mean it's going to drop a boolit anywhere near .309. See what they drop in the alloy you intend to shoot. 2nd- Why do you want to go with harder than WW alloy?

Given your dimensions I would try a sizer in the .310 area first, if your gun will accept the loaded round that is. If you are lucky and the boolit drops at around .310 you can try shooting them "as cast, that is with no sizing by running them through a slightly oversize die to apply the GC or only partially running them into the die base first or trying the old snap the GC on and shoot trick, with lube of course.

[Doc Highwall]

I would try the boolits sized at .310 to fit the throat.

[lead-1]

Wayne, I used an oddball hollow point bullet I had laying around as a slug instead of a egg shaped sinker so these are the dimensions of my chamber and barrel. The only sizer I have at the time is a .308 LEE push thru. I thought if I was to harden up my WW some I could push the rounds a little faster, maybe I don't need to? I guess I will cast up some actual bullets with this mold and see what size it drops and compare the chamber slug to the cast bullet.

[docone31]

I think, possibly, sizing to .308 will produce a lot of leading.
You should size to .309 at least.

[snaggdit]

I increased the size of several of my Lee push through sizers by pushing some boolits through with fine valve grinding cpnd. Took about 30 pushes to get +.001 but YMMV. I checked every 10 or so. Since Lee doesn't make every possibility, this allows you to custom one for your needs. It really wasn't hard and only took me about 15 minutes each. Now I have a .309 for the 30-06 (slugged .3075) and a .313 (slugged .311) for the SKS.

[Bret4207]

Wayne, I used an oddball hollow point bullet I had laying around as a slug instead of a egg shaped sinker so these are the dimensions of my chamber and barrel. The only sizer I have at the time is a .308 LEE push thru. I thought if I was to harden up my WW some I could push the rounds a little faster, maybe I don't need to? I guess I will cast up some actual bullets with this mold and see what size it drops and compare the chamber slug to the cast bullet.

Dear Lord, give me patience. Look, this has been stated a zillion times here- hard lead does not equal faster speeds. It's not that simple. I can take straight WW to 2200+fps with ZERO leading and 1.5" accuracy at 100 yards, other are shooting boolits in the 8-9 Bhn at factory speed. So please, just try WW first. You have a long, long learning curve before you need to worry about juicing your alloy. Lets start with casting premium boolits, fitting them to your gun and working the kinks out at that level. I'm not picking on you or trying to be nasty, but it seems every single week we get someone doing what you are, so apparently we aren't getting the message across- Fit comes first. Hard alloys don't equal high speeds. Fit is king. lousy boolits equal mediocre groups. Start with the basics first- quality boolits that fit your gun.

[lead-1]

Whoa, whoa, whoa take it easy on that head, its the only one you get. I was under the impression that it took harder alloys to get closer to jacketed speeds but I would be happy in the 2200 fps range from the '06, actually tickled pink. Actually it sounds better that I don't have to mess with mixing metals for a while.
I will read threads until my head hurts and my search function just don't seem to get me what I am looking for, a lot of times it is a matter of one word being being off, ie, bore slugging and chamber slugging, I was actually wanting to match an artical I had read to the picture that I had saved. I am getting great info on this thread, now I know how to resize my sizer die that I had origanally bought to resize out of round jacketed military bullets. Since I have a .310 measurement on the chamber throat (?) I will cast a few bullets and check for size, if they are .309 should I beagle the mold to .310 or try the bullets at .309?


Thanks guys for the great input here.

[Maven]

lead-1, I also have a Win. Mod. 70 (ca. 1980 or '81) and a Lee C-309-180R. The problem is my Lee mold and Lyman #311291 cast too small to fit my rifle and accuracy with either is only so-so. What you can try is casting, say 5 - 10 boolits with your mold and when cool enough to handle, try to insert the nose into your rifle's muzzle. If it meets with resistance and leaves rifling marks the length of the nose, you're probably in good shape. You may also want to oil your bbl. and then try reslugging it with one of the freshly cast Lees (grease the boolit as well). If slugging indicates you'll need to size to a larger diameter, it's not difficult to open a Lee sizing die a couple of thousandths of an inch. (We have a sticky on it somewhere, or you can look on the CASTPICS site (bottom of your screen) for instructions. I don't know about 2,200fps, but there are plenty of midrange loads (1,700fps - 1,800fps) that are very accurate. Hope this helps!

[runfiverun]

always,always,always..try as you go.
i have a few h/v loads that work best with a slip fit in the bbl. h/v is when you go over 2200 fps.
most of my other rifles are 1-2 thou over groove diameter.
however the fit of the boolit to the throat will almost [90%] always trump what the bbl tells you to do.
even after fitting and measuring everything the rifle still won't shoot the boolit [sigh]
and it might just want more bearing [body] and less nose contact.
thats why most of the serious guy's on here have 5-6 30 cal molds by various manufacturers.

and I like brett spend more time on other boards explaining how a boolit with a bhn of 10 will go to 1600+ fps with a plain base,and one of 16 will go over 2k with a gas check.
but thats why we are here together to help each other figure out this cool stuff.
start with something change one thing at a time and it will slowly come together.

[Bret4207]

I'm sorry if I came off too hard, I wasn't trying to be. It just seems we aren't getting past the advertising hype about hard boolits. Work your way up from the 12-1400 fps range and see what your gun tells you. It might say it wants a harder alloy but there's just as good a chance that with a properly fitted boolit and maybe a little water quenching you can get upwards of 2 K or more. I don't understand the idea of rushing to add tin and antimony to an already good alloy if it's not needed. Hard alloys can work fine at low to high speeds but why go to the trouble and expense if it's not needed? The sales hype sure has worked on this one!

[lead-1]

No no, Bret, not hard at all. I guess that I have been a little threw by loading cast handgun bullet and being told not to go over 12-1400 fps so I figured same lead in a rifle would be same velocity. I just got back from the range to try two loads that I already had loaded both with .308 sized cast bullets,

4 rounds 13.5g Red Dot, CCI 200 primer, 185g spitzer type lead w/alox and gas check at a COL 3.245
4 rounds exact same round but 16g Unique

The best load by far was the Unique and it was a 12 shot vertical string right on the windage and this was at 50 yards. The same loads thru my 03-A3 at 100 yards gave me one hit on the target out of eight. I will try to get a handful of bullets cast with the 160g mold and see what happens with them in the next couple of days.
Will the LEE liquid ALOX be sufficiant lube for these or should I do a pan lube type lube.

BTW the rounds fired today had like 6 of 8 rounds that were not really keyholed but were not round holes.

[Bret4207]

They were sized .308? Too small I'd bet. I regularly size .311 for several .30 calibers. I'd try at least .310. The non-round holes mean the boolits isn't stabilizing, possibly (probably) because the boolit is too small to seal and get a good grip from the rifling. Your OP says the barrel is .308 to .310 so I'd aim for trying .311 or .312 at a later date. What we measure and what the barrel wants aren't always the same thing. Also remember that a tight spot in the bore can make a .310 barrel look like it's a .308, but the rifle still needs that larger boolit.

[lead-1]

Gotcha, now when I get to try a bigger diameter bullet will LEE Alox be an OK lube or should I use a pan type lube? I have both types.

[snaggdit]

The adage change one thing at a time is a good one. If sizing larger doesn't improve it, then try a diff. lube. Although you might want to try +- powder loads first after sizing larger.

[lead-1]

I am hopeing that the bullet size works but I wasn't sure if the Alox was a good lube choice for this type of bullet or if it was more for pistol bullets.

[MT Gianni]

Try the alox first. It works OK in a few of my applications but is bettered in all by other wax type lubes.

[Bret4207]

Ditto what the other guys said. Also, make sure that barrel is free of ALL fouling. Use all your favorite concoctions to clean it then get in there with some 4/0 steel wool or Chore Boy on a worn brush and scrub her good, then go back with the solvents again.

I wouldn't worry about the bore/groove size too much. The throat is what you size to. No matter what we do as far as sizing, the final sizer is the powder/throat combination. Fit the boolit to the throat. The only caveat to this is the extremely rare grossly oversized throat, but I doubt you'll find a Winchester 70 with that problem. So if your throat is running .310 I'd size at .310 and maybe try .311. Now .311 may sound too fat, but often our sizers run a tad small or the alloy doesn't size down quite as much as we think or our tools are off half a thou, you can try .311 as see if it chambers okay and the nose allows it. This is where undersized mould rear their ugly heads. Get one of those and then we have to take another route.

[lead-1]

OK guys I went out this morning and finally actually cast a couple of boolits for myself. I cleaned my molds with brake cleaner then to the boiling water with a toothbrush and dish soap, after drying them good I used a candle to smoke them up real well. Fired up the LEE production pot IV and burnt the oil off of it and put in about six pounds of WW ingots, when it got about 750 degrees I fluxed with a little fine saw dust. I cast about 38 boolits and saved 30 of the .30 cal. 160 grain and cast about 56 boolits and save 50 of the .44 cal. 240 grain. When I get this matching the boolits to the gun thing down, this might get addicting, LOL.

I randomly picked out ten of the .30 cal boolits after they had air cooled for an hour or so and ran each one thru two different calipers at different spots. I'm sure that you know what I mean when I say they are not perfectly round but I may have lucked out as the predominant measurement (80% or more) is .311 with .310 and .312 spots, mostly of the .312's were on the casting line where the two mold halves meet. Measured each boolit in four spots with each caliper.

I think my next project is to push some jacketed bullets with valve grinding compound thru my .308 sizer to get it to at least .310 diameter. Sorry for the long post but I may be getting somewhere here, thanks guys, keep it coming.