Hard Cast Bullets in 30-06 -- Trouble getting a decent group!

[Jim_K]

All,

I've just decided to join this forum after over a year of using it for information. Many thanks for all the good useable advice I've received to this point.

I am working up a 30-06 hard cast load for an M1917 Eddystone. It is standard configuration, 26" barrel, 5 grooves. Seems to shoot 150 & 180 grain jacketed bullets okay. But...

I'm nearly unable to group 5 shots of 165 gr RNFP (no gas checks... yet). These are hard cast from SlashK, they purport that these bullets are 15 on the SAECO hardness scale (~35 BHN). They're .308" and 0.93 inches long.

I'll explain what I've done so far and hopefully someone can point me in the right direction.

I've loaded these buggers with 18 gr Alliant 2400 to 3.050" COL. I put a heavy crimp on these rounds and they shot terribly. Something like 18" 5 shot group at 35 yards. No key-holes but these things are high, low, port and starboard from where I'm asking them to go.

Finally, I changed two things at once (very scientific, I know!). 16 gr Alliant 2400 and zero crimp. This yielded a better group, maybe 5 inches. Still a long way to go.

Any advice or hints would be much appreciated.
Thank you, Jim K.

[s mac]

What size is your bore? You boolits need to be .01. .02 larger than your bore. .308 is most likely too small.

[petroid]

I would start at about 13 grains of 2400 and work up to 16. And only use a light crimp. 2400 is a pistol powder. It doesn't need a heavy crimp to build pressure like slow rifle powders do. The crimp is really only to prevent bullet setback from recoil which should be minimal. Also you didn't say what your bore slugged at and how the bullets were sized. An undersized boolit will not be accurate. If the above doesn't help, try some gas checks. If its a gc boolit it may not be supported well without the check.

[HARRYMPOPE]

My Eddystone and Winchesters(5grv and 4grv barrels) like .311 bullets and do well with from 16-22g of 2400.I doubt the hardness has as much do do with it as bullet size as mentioned above also.Unless you have the apparatus measuring a 5 groove barrel will be tough from a slug.You dont need to slug the bore just seat as big of bullet that will chamber and shoot it.Even after you know the dimensions that's all you will do anyway.My buddy used .315 dia with a 303 nose in the P-17.

If using no GC 10-12 g is a proper load.

[RPRNY]

.308 and über hard cast is not a recipe for success. I bet your Eddystone has a generous throat. You need to check and clean the barrel for leading; I'm betting you have at least some smear on the groove edges. Slug your bore and throat. Try to fill the throat or at least go @ .003" over bore diameter and at under 2000 fps, I would use a softer alloy, like 18 -21 BHN so as to get some obturation.

[Blammer]

I'd start with a .310 dia projectile and no crimp and see how it does.

oh yea, are these GC bullets and you're not using the GC? or are they plain based?

[Jim_K]

Thanks everyone, I'll try out some larger diameter bullets. Being that there are 5 grooves, I have not tried slugging the barrel.

If I seat these bullets really low, about 3.050" COL and cycle them through the rifle unfired, I get 5 very light witness marks on them from the rifling.

If I seat them very high ~ 3.210" COL and cycle them through, I get 5 heavy witness marks, basically flattened out segments on the bullets. I think they're fitting in the bore but they may be too small to snug up really well so I'll try out some larger .309s or .310s as well.
I'll also try going down to 13 gr of 2400 and working up toward 16. Gas checks have been ordered and will be installed as soon as possible thereafter to see what if anything they can do for me.

Any other thoughts please let me know, I'm just starting out with hard cast in rifles, so I've got a lot to learn.

[Jim_K]

Blammer,

These particular bullets are bevel based,

[nicholst55]

Once you lower your powder charge and install some gas checks, try some slightly softer bullets. The term "hard cast" was coined by commercial bullet casters as a sales ploy. They cast their bullets harder than woodpecker lips so they won't be distorted during shipping. That is the only reason they're so hard.

[jbltwin1]

I suppose you actually WEIGHED the bullets to verify that they are close to the same WEIGHT? Mike.

[MT Gianni]

Even being that hard they are far less than the hardness of an aluminum can homemade check. You cannot put a regularly designed check on a bullet without a check shank so that is out. They may do OK @ speeds under 1600 FPS but even at that point they are too hard for that speed.

[waksupi]

Gas check first. Second, I am betting you need a larger diameter.

[Jim_K]

I suppose you actually WEIGHED the bullets to verify that they are close to the same WEIGHT? Mike.

Mike,

I weighed a small handful and they are between 164.2 gr and 164.5 gr.

Thanks,
Jim K

[45-70 Chevroner]

No GC chank no GC. You can't put GC's on a bevel base. HARRYMPOPE has the right answer. 10 to 12 grs. of 2400 and you will probably see a lot better results. You could even try Unique at the same grains.

[MtGun44]

First: Why do you call it a "hard cast load"? This immediately makes me wonder if you are
off track to start with, imagining that "hard" is a major factor in this, and of primary
importance to success. It is not.

You need to FIT the boolit to the gun - at least to the groove diameter plus a couple thousands,
and in rifles, it helps a lot to fit to the throat to align the boolit properly at launch. .308 is
almost guaranteed to be TOO SMALL - add in TOO HARD (35 BHN!!) and you will not
likely succeed. For a .308 groove diameter, you will want .309 at least, and many find
.310 to .311 works best.

Hard may be OK, harmful, or helpful - but is NOT a primary consideration and you are
using the term "hard cast" like the nutball commercial casters do, and they know next to
nothing about making boolits. A softer boolit with a GC AND fit properly is much more likely
to succeed in a rifle.

Fit, design, lube are all critical to success, "hard" may be necessary as you push the rifle
faster and faster. Ordinary air cooled wheel weights works fine for moderate loads in the
1700 fps or so range.

Bill

[Blammer]

are you waiting on GC's from me?

[Jim_K]

Bill,

I'm aware of the commercialization of the term "hard" cast. I assure you I'm not a nutball, although I'm not sure I'll be convincing anyone of that. Part of why I'm using that term is because I'd get the same reaction in the opposite direction if I simply said "lead bullets" So I'm not sure how I can win this one with you.

All,

A partial update: Tested 12.5 gr 2400 and had even better success than 16 gr and far more results than the 18 gr.

I do have IMR 4227 laying around as well, and 4198 (which I use in .223 rem) if that gives anyone additional thoughts. After that is just my jacketed load powders (IMR 4895 and 4350) All of this was done with neck sized brass bell'd to avoid shaving the alloy while seating it.

Thanks,
Jim K

[HARRYMPOPE]

Same charges of 4227 for plainbase 10-12g shoot well in the 30-06.Bullet weight from 150 to 200g.

[Adk Mike]

I've shot thousands of cast thru my 1917. 314299 @.311 or 311644 @.311.13 grains of Unique. I try other loads every month but that Unique load works good.

[runfiverun]

if this is the magma bevel based 165 rnfp that just about every commercial caster sells, you actually can put a gas check on it.
I have the mold and I have put some on and tried it.
it don't shoot much better with it, but it does take and keep one and you can push the boolit a bit faster.
anyway these boolits were designed to be used in 30-30's at sedate velocity's for cowboy action shooting out to 50-100 yds.

[petroid]

Glad to hear you're getting better results! I agree that a fatter boolit will likely work better as long as it wil chamber.

[Larry Gibson]

No GC chank no GC. You can't put GC's on a bevel base. HARRYMPOPE has the right answer. 10 to 12 grs. of 2400 and you will probably see a lot better results. You could even try Unique at the same grains.

Actually I would use Bullseye and try from 6 - 8 gr.

Larry Gibson

[45-70 Chevroner]

if this is the magma bevel based 165 rnfp that just about every commercial caster sells, you actually can put a gas check on it.
I have the mold and I have put some on and tried it.
it don't shoot much better with it, but it does take and keep one and you can push the boolit a bit faster.
anyway these boolits were designed to be used in 30-30's at sedate velocity's for cowboy action shooting out to 50-100 yds.
Thats a new one. It must be the shape of the bevel. One I was not aware of.

[runfiverun]

it tapers down to the same diameter as a 30 cal gas check shank [.284] at least my mold does.

[MtGun44]

You misread my post. I did NOT call you a nutball, but the commercial casters are on this subject. I
would never make that sort of unkind and uncalled for comment about a member here.

We usually hear excessive interest in hardness as a primary way to avoid leading amoungst the beginners.

Focus on fit, lube and proper powder charge selection for the design and leave hardness as a fine tuning
issue for later. As hard and small as that boolit is, you'll need to whack it pretty hard with some FAST
powder to try to get it to upset to fit better. Red Dot at about 8 gr, working up to 13 gr should work fairly
well, as should try about 7 gr working up to 10 gr of Unique. You'll likely have better results with a GC
boolit of .310 or so diameter and cast of a softer alloy, around 14 BHN or so like air cooled wwts. Save
the super hard for the 2000 fps class of loads where it may actually be needed, although I think the small
diameter will still give you trouble.

Bill

[mikeym1a]

Back to the basics. From the posts, I see a 'hard' boolit of uncertain fit. No gas check. Relatively high powder charge. A heavy crimp. 'Hard' boolits do not necessarily grip the rifling better, and without a gas check, might lead to leading of the bore. I'm not sure where the line is, but, somewhere around 1400 - 1600fps, you need a gas check. While the boolit might be the nominal diameter, each rifle is different, and you must also consider the throat of the chamber. Also, a heavy crimp can reduce the diameter of the boolit. SO, try and determine the groove size of your barrel. DO try and do a chamber cast to determine your throat diameter. I have read that you need to fill the throat with the boolit for best performance. Adjust your boolit speed to that suggested above, until you get one with a gas check shank. Did I miss anything? I hope this helps. Nothing new from me, just trying to clarify what all the rest were saying, and put it into one post. Good luck. mikey

[leadman]

If you drive a boolit thru the barrel it should show signs from the lands and grooves. If it shows only marks from the lands you then know the boolit is too small.
I'm surprised Larry did not mention it but a poly-fil filler may help the accuracy. Use about 1 gr. and push it in the case with a pencil and seat the boolit so it touches the rifling. I have used this when the bore was larger than any boolits I had available and it worked pretty well.
The Grex shotgun filler is reported to also do the same thing.

[4rdwhln]

My 1917 has open sights so for now my experiments in 06 have been reserved to the model of 1903. I have learned much from this form. I have made the pound casts as well as slugged the barrels on both of these rifles as well as my 30-338. 2 things jumped out at me right away from doing this. 1 the 1917 I have has much more pronounced rifling than the 03. It also starts sooner, or closer to the brass when loaded. We did the 30-338 3 times only to find it has allot of free bore. I have taken allot of measurements with the micrometer on the casts and slugs. however I think a person can gain a whole lot from just looking at the slugs.I can clearly see the amount of grip the rifling has on each bullet the shape of the chamber and throat and how well my load matches up to the chamber cast. I believe this is and a whole lot of reading on this form is why my first 5 loads with unique and 4227 powders have resulted in 1 inch average groups of 5 shots at 50 yards. I am using the lee 309-170 mold sized at .310 and gator checks. I also have been using my first batch of Ben"s red lube. so far I have shot 25 rounds and then 1 wet and 1 dry patch for cleaning. next trip out it was 18 rounds and no reason to even run a patch down the bore. It was spotless. I have sorted my bullets into .1 grain increments as well as weighing and labeling my sorted brass and shooting it in sequence from lightest to heaviest. I have been using 50 ww-50pb+2% tin,air cooled. I have a bunch of water dropped. I am saving for when I make the jump to higher speeds. So far I have found nothing but great advice and an abundance of help here.
P.s. a guy should check out the cooking section as well, Lots of good found there also.

[Larry Gibson]

Didn't recommend a dacron filler because with the faster burning Bullseye I recommend for bullets such as the OPs the filler is not necessary or needed. Now with a softer FB'd bullet of proper diameter the low end 2400 loads mentioned would benefit from the dacron filler. However, that is not the bullets the OP has and is asking about.

Larry Gibson

[Outpost75]

If you upset a throat slug, and measure the diameter of the ball seat ahead of the case mouth, before the rifling starts, THAT is the diameter you should size bullets to. Most M1917 .30 cal chambers run large in the throat, and will do best with a bullet of .312-.313", cast no harder than 12 BHN, and for a plainbase load which shoots well without gaschecks or filler, work in the range of 6-8 grains of Bullseye, 8-10 grs. of Unique or 11-13 grs. of #2400. We shoot many thousands of these for Appleseed classes in the Springfields and US Enfields with fine results around 2 inches at 100 yards in most rifles.

[Marlin Junky]

What size is your bore? You boolits need to be .01. .02 larger than your bore. .308 is most likely too small.

Yeah, .308" is not gonna work with any normal load. Perhaps if the alloy is very soft and the powder charge is very light you might get a couple inches at 50 yards.

A SAAMI '06 chamber is .3106" just ahead of the case mouth. Approx. 0.311" boolits work best for me.

MJ

[geargnasher]

Ben shoots a lot of tiny groups with plain-based boolits, the trick is 1400 fps and some attention to detail. He does this with just about any medium-to-slow pistol powder, it doesn't seem to matter which one.

Check out the threads he's posted about it, or send him a PM.

BTW, Outpost75's recommendation to make a pound cast of the rifle's throat is spot-on. Do that and don't worry about the groove/bore diameter.

Gear

[williamwaco]

Too Small and Too hard.
A perfect storm.

You have the answer in the posts above.

10 to 12 grains Unique

Or

14 to 16 grains 2400

Sized to .310 or .311 will get you into the 1.5 inch range. ( But NOT if you are using a gas check bullet with no check. )

( Unless the rifle is faulty or there is an operator error. That last one causes a lot of large groups in my case.)

[Jim_K]

Quick update to everyone,

I was able to recover a handful of fired projectiles from the field behind the target area, and upon inspection it was clear that these are not the correct diameter. Two grooves are plainly visible and the other side of the bullet is untouched. I sacrificed a 12 ga 00 buck load and slugged the bore, confirming that it measures approx .310

Thank you so much everyone for your help and input, I will simply need to use increased diameter bullets if I choose to continue using cast bullets in this particular rifle.

[detox]

I would use the fatter Lyman 314299. This bullet shoots verygood in most. Load it long so that it is shoved into rifling...this will help center bullet on takeoff and reduce wobble down range. I have used 20gr of 2400 with verygood results in my 308.

The Hornaday 30 cal gas checks fit this bullet perfect. I size bullet and crimp GC in LEE .311 sizer. VLD Chamfering and Flaring of case mouth with Lyman M die will help seating.

[petroid]

If you want, I can send you some boolits to try out of my Lee C312-185-1R mold. It drops about .311 so I can send you some unsized. Problem is they are slightly out of round being up to .314 on the fat side. My .309 sizer actually puts out at .310 so those may work for you or I can powder coat some and size to .310

[MtGun44]

With a .310 groove diam, I'd start with .312 and then try .313. I think
you may succeed with .311 but it will likely be right on the edge of too
small.

Bill

[MUSTANG]

Jim K:

Have not been working with my M1917 for a couple of years, but here is some data I pulled from 2 years or so. Groups are not great, but they were shot using the M1917 iron sights. My groups for this rifle are not the small size many here have achieved, but I have not yet put the load development effort in this rifle to shrink them either.


Following Target is from 100 Yards. 190 Grain Lyman 311644, sized to .311. Used 21 Grains of WC846 powder with a 1/4 Sheet Toilet Paper filler over the powder. .014 Aluminum Gas Check. Average Velocity was 1539 FPS. (BLC-2 has close to same burn rate as WC846)
101314

This Target is from 100 Yards. 165 Grain RCBS 308-165-Sil sized to .311. Used 26 Grains of WC846 powder with a 1/4 sheet Toilet Paper filler over the powder. .014 Aluminum Gas Check. Average Velocity was 1725 FPS.
101315

How do your groups compare to these efforts?

[1Shirt]

Larry and MTGun as usual have it right. Proper fit being the key to most cast rifle blts regardless of hardness. Most of the mil surp 30's will shoot best with at least .311.
1Shirt!

[pls1911]

Worry more about bullet size fit-to-bore and than hardness.
Bullets of any reasonable hardness should shoot well if sized .002 over bore, gas checked, and not driven too fast for the alloy.
My .30 cal rifle bullets are in th normally heat treated to 20-25 BHN, gas checked, and sized .312.
2100 fps and slower, I've never had problems with poor accuracy or leading... none.
My own best accuracy hovers around 1700-1900 fps.
And they slap pigs as well as any.30 cal in the field.