Poor first outing with precast in 30-30, 308. Diagnosis?

[Backcut]

Greetings! Thanks in advance for any advice, or if you can point me to any stickies that'd be helpful. There are many.
I had a very poor first outing in .308 and 30-30 using precast lead boolits, abysmal accuracy. Could use help diagnosing my errors.

Background:
I previously had decent success with reduced loads in .308 win and 30-30 using Speer 100gr half-J and 110gr TMJ 30 carbine bullets, with reduced 4895 loads, Trail Boss, and 2400. Got around 1.5" groups from the bench at 50 yards, good enough for plinking. Next I wanted to try cast. I have never shot any cast boolits before in handguns or anything else.

I got some .309 precast boolits from Rim Rock, which I believe to be good quality. My poor performance is no reflection on these nice boolits.
For all loads, I used a Lee universal case expander before seating, then crimped with a Lee FCD.
I measured the boolits at .309. The boolits are advertised as coming with magma lube.
I pulled them out of the box and seated them over powder, crimped, and shot. 5-shot groups.

Winchester 94, 1980s manufacture, shot very little.
FC brass, CCI 200 primers
Rim Rock 165gr hard cast RNFP. Advertised 22 BHN, magma lube.
Seated to crimping groove, moderate crimp with Lee FCD.
Powder: 2400
15gr 1650fps 8fps sd
17gr 1769fps 16fps sd
19gr 1919fps 20fps sd


Ruger American 308 Win
PPU brass, CCI 200 primers
Rim Rock 115gr hard cast RN. Advertised 22 BHN, magma lube.
Seated to OAL 2.450", moderate crimp with Lee FCD.
Powder: 2400
16gr 1725fps 20fps sd
18gr 1867fps 6fps sd

Powder: Unique
12gr 1801fps 11fps sd
14gr 1971fps 8fps sd
16gr 2137fps 7fps sd


I shot all of these from the bench at 50 yds, in 5-shot groups. The chrono results were consistent and I was happy with the velocity sd, but accuracy was abysmal. I was all over multiple sheets of printer paper with shots a foot apart at times. Accuracy was bad from the start, it didn't get any better or worse as I went.
After shooting my cast loads, I did 4-5 shot groups of factory Rem 150 in the 30-30 and surplus 147 in the 308, and got close to 1" groups, just to confirm nothing else is wrong.

I think I'm going to set aside the 308 for now, and focus on seeing if I can get the 30-30 to shoot these cast boolits.
I'm not sure how to tell if I'm getting excessive leading, most of the threads I've found on that talk alot about forcing cones. Peering down the barrel I don't see anything that jumps out.
Do I need to slug my barrel(s)? I figured these are relatively new rifles, fired little, with no microgroove or any other funny stuff, and the basic off-the-shelf precast ought to shoot ok at .309 or they wouldn't sell many. These rifles both shoot just fine with my handloads with speer/hornady/whatever .308 projectiles.
Am I at the wrong velocity for my BHN? Manufacturer's FAQ says you can run the 22BHN boolits up to 2200 fps, and I never exceeded that.

I'm thinking there ought to be a way to get the boolits I've got to shoot acceptably well or at least better than this in my 30-30. What should I try next?

Many thanks,
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[Larry Gibson]

Apparently you are using the plain based (not GC'd) bullets from Rimrock?

If so you are simply pushing them too hast. All of your loads and velocities are GC bullet velocities. Suggest you use load data with velocities in the 1000 - 1400 fps range.

Rimrock also sells a GC'd 30 caliber bullet. You might try those next time.

[MostlyLeverGuns]

I have not been able to push commercial cast PLAIN BASE very fast in my 32 Special, 30-30 or 308. 1000-1200 fps has been about the best with decent accuracy. Wind also really pushes them around at those velocities on my North-South range with a prevailing Wyoming west wind. With good gas check bullets from Leadheads, Matt's, Bullshop I can get full velocity with accuracy in the 32 Special and 30-30. Haven't tried Oregon or Rim Rock gas checked but would expect the same.

[Win94ae]

In my 30-30, (1 in 12 twist;) I shoot gas checked cast bullets at the same velocity as jacketed bullets. I actually use the same load as my 150gr jacketed bullets.

Twist rate can make a huge difference, so if you have a 1 in 10 twist, you might not be able to get over 1900fps with good precision. The rpms may cause the bullets to fragment.

Good luck!

[zarrinvz24]

To the OP, you mentioned this is your first experience with cast projectiles. I'm not sure if you knew this going in, but cast bullets at rifle velocities is significantly more difficult to master than handgun rounds. The bases of your bullets are likely melting at that velocity. I'd recommend you further reduce charges to start with a velocity between 1100-1200, then slowly work up from there. Commercially cast bullets are hard with a hard lube - this could be contributing to your problem as well. I am far from the expert, but those are some suggestions to try.

[Backcut]

Thank you for your replies. Yes these are the plain base. I am not likely to try factory GC bullets anytime soon as the price seems comparable to or more than J bullets. Maybe if I progress to casting my own, I can try adding a GC. First I'll see if I can get my feet under me with the precast plain base.
For now I will slow these down and try again. Hope to post an update next week.
Thanks again,
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[white eagle]

Do you know the quality of the lead you bought from them?
also the size are they consistent?
you should also use a gas check when you try to push boolits fast
Like Larry mentioned
personally you may want to get a mold and make your own you just don't
know what you are getting when you buy from a place that has to
accommodate a vast array of guns
one size doesn't fit all

[popper]

Try 9 1/2 - 10 gr unique with those PB, 2400 same load works better. Just too fast. 309 is probably too small, most use 310 or 311 if marlin 30/30.

[Mk42gunner]

You need to check for leading before you shoot any jacketed bullets.

All of the plain based projectiles I have shot through .30 caliber rifles were made from air cooled wheel weights, at about 12.5 BHN. A small charge of handgun or shotgun powder gave velocities in the range of 900-1250 fps.

Doesn't sound very fast, but a 120 grain RNFP at 1250 is a decent .32-20 equivalent, and I was just using these for plinking anyway. They would be very good for small game at typical .22 rifle ranges, i.e. under fifty yards.

Oh yeah, I also sized them to .311".

Robert

[ABJ]

Try 9 1/2 - 10 gr unique with those PB, 2400 same load works better. Just too fast. 309 is probably too small, most use 310 or 311 if marlin 30/30.

What Popper said and other powders in the Bullseye/Red Dot range around 5.0 to 6.0 will be 1000 fps give or take. .311 is my go size, I don't own a 30 that will shoot .309 accurately.
Tony

[wmitty]

Backcut

Welcome to the forum! Others with more knowledge/experience than I have already commented regarding the velocity limitation of the plain base boolits. It may be that the expander plug diameter in your sizing die is small enough to allow sizing down of your boolit by the case neck; or the factory crimp die is sizing the boolit down. The case neck should hold the boolit in place, but not squeeze it so tightly that it is distorted. With the hard alloy being used this may not be happening, but it is something to watch for. Also, seat the boolit with the ogive/ nose touching the leade (tapered portion of rifling). This helps align the cast boolit and aids accuracy.

[scattershot]

This was three shots into two holes,using 5.5/RedDot and a 165 grain cast plain based bullet. Marlin 336, 50 yards, bullets sized to .311. Maybe try a larger diameter bullet.

[rintinglen]

Try 7 to 8 grains of Unique, in your 30-30 with either boolit. I have loaded thousands of 311-245 95 grain boolits, along with a pretty large pile of 3118 boolits, over 8.0 grains of Unique or Herco, whichever I had to hand. I have also loaded 170 grain 311-291 boolits, albeit with gas check over the same charge. All of these would shoot 2"-3," 10 shot groups at 50 yards from several Winchesters.

[fiberoptik]

I’m surprised no-one has made mention of cleaning out al the copper in your barrels before trying to switch them to cast....


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[gwpercle]

Your sd numbers look very good , especially the Unique numbers ... Try this :
1.) Give the barrel(s) a good cleaning to remove all copper ... get it as clean as you can .
2.) Use a boolit with a Gas Check !

I'm willing to bet money that your groups tighten up .
If you buy a mould ... buy one cut for a gas check ... they make a huge difference in rifle groups and make your like easier in general .
Trust me on this ...and fire a few cast boolit shots to get the barrel conditioned before you start testing your new loads ...cast hardley ever do their best from a squeaky clean barrel .

Some people treat gas checks like they are rattle snakes but me and Skeeter Skelton find them useful in the right places .
Gary

[charlie b]

I'll add that the vel is probably too high. When I shoot plain based and lubed bullets I keep the vel below 1200fps. I find that even powder coated plain based bullets like the lower velocities better.

FWIW, I had the same experience as the OP with commercial hard cast in the .30-30. I tried some 1500fps loads and got leading in the barrel and horrible accuracy. After cleaning and loading some at 1100fps the groups got down to the 1" at 50yd level.

[Soundguy]

Agree with the others. P b bullets and no gc and you are probably 600_700 fps fast. Go gc or slow them down. I shoot my own 30 cal and 8mm gc rifle bullets and get better accuracy than factory generic ammo.

[garandsrus]

My two most common 30-30 powders and charge weights are 10gr Unique or 8.5gr Red Dot. I am shooting a 160gr gas checked bullet but I think they would be fine with a plain base. You could go down a grain or so to start. These shoot great and are easy on the shoulder and powder can.

[Backcut]

Thank you to everyone for your good advice!
Took me long enough to make this update, but my second outing went much better after slowing way down. We have redefined what I thought of as "rifle velocity".
So now that I'm on paper, there's still work to do and I'll have to start casting my own once I shoot up these precast. I've started making ingots and once I build up a stash can start shopping for molds and other equipment.

Thanks again!

50 yards

[gwpercle]

ATTABOY !
Very nice , improvement is evident .
Finding a mould might be hard , Titan Reloading, Midway USA and Lee Precision all had "out of stock" on the Lee C309-170-F double cavity I use in 30-30 ... they are/were usually easy to find !
Keep looking ... I don't know where all the moulds went but I hope they return soon .
Gary