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Good idea on bell curve for culling boolits......

Are you having any issues with the bases of the Mihec boolits? Getting a clean base and square gas check has gave me fits, most bases are a tad over sized for the check.

As far as lubes go, I'm running White Label BAC and Carnuba Red in a RCBS lube/sizer. Being in Florida our temps routinely run between 70 - 80 degrees this time of year, I haven't seen any wax issues. No leading issues either with WW's air and water quenched. I've not tried to add a harder alloy, yet.

Not a problem with Hornady Gas Checks. In fact, prior to sizing thru my Lyman 450, some of the checks were a bit loose.
I did however use "old" gas checks:

hornady box gas checks.jpg

I also have a box of "old" Sierra gas checks.
When they run out, I'll be making my own. I have a "Checkmaker" idling on my shelf.
 

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I've had no time to go to the range. But I do have some cast loads to try out in 6.8 gun #2....
 

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Good idea on bell curve for culling boolits......

Are you having any issues with the bases of the Mihec boolits? Getting a clean base and square gas check has gave me fits, most bases are a tad over sized for the check.

As far as lubes go, I'm running White Label BAC and Carnuba Red in a RCBS lube/sizer. Being in Florida our temps routinely run between 70 - 80 degrees this time of year, I haven't seen any wax issues. No leading issues either with WW's air and water quenched. I've not tried to add a harder alloy, yet.
I've also noticed the problem with the gas checks on the Mihec bullets.
A real booger to get them on.
The 6.8 mold I got from Lee has not had this problem, they snap right on.

Still would like to hear from anyone who has experimented with AA1680 & AA5744 powders with these lead bullets
 

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BB can you measure some of your un-sized Mihec casts. Mine are coming out .284 on the driving bands before sizing to .278......Very tempted to try a 7mm gas check and size those down. I'm reasonably sure some of the flyers I'm getting has something to do with the fit of the check. ...... I haven't tried the 1680 or 5744.
 

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Based upon my experience, higher velocities are need to properly stabilize these pills. I have pretty much maxed out my velocity at 2600 fps. Starting to see pressure signs. I have much better down-range accuracy with my Ideal/Lyman 110 gr. cast. The length of the Mihec 130 gr. cast puts the gas check well below the neck of the cartridge. I buffer with Dacron. When it stops raining sideways, I will be getting out to the range to try out a soap-based lube on the Mihec 130gr. Might be able to get better velocity, S.D numbers, and down-range accuracy. The soap-based lubes have helped me out considerably with my Marlin 444S. Low and high temp stability.


Info on lube quest:
.http://castboolits.gunloads.com/showthread.php?148746-quot-Extreme-quot-boolit-lube-The-Quest&

Takes a while to get to the meat.

I've settled on a SL lube series variant: 4 oz.Tranny Goo, 4.5 oz. Williams Mug Shaving Soap, 4 oz. Bee's Wax, 1 Tbs. Synthetic 2 stroke oil, and 1 Tbs. mineral oil.
 

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Based upon my experience, higher velocities are need to properly stabilize these pills. I have pretty much maxed out my velocity at 2600 fps. Starting to see pressure signs. I have much better down-range accuracy with my Ideal/Lyman 110 gr. cast. The length of the Mihec 130 gr. cast puts the gas check well below the neck of the cartridge. I buffer with Dacron. When it stops raining sideways, I will be getting out to the range to try out a soap-based lube on the Mihec 130gr. Might be able to get better velocity, S.D numbers, and down-range accuracy. The soap-based lubes have helped me out considerably with my Marlin 444S. Low and high temp stability.


Info on lube quest:
.http://castboolits.gunloads.com/showthread.php?148746-quot-Extreme-quot-boolit-lube-The-Quest&

Takes a while to get to the meat.

I've settled on a SL lube series variant: 4 oz.Tranny Goo, 4.5 oz. Murphys whisker soap, 4 oz. Bee's Wax, 1 Tbs. Synthetic 2 stroke oil, and 1 Tbs. mineral oil.
I don't mind chewing on some of the fat to get to the meat that might be near the bone, but do you mind helping a feller out by tell me at what part of the 139 pages of that post should I start reading?
 

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I don't mind chewing on some of the fat to get to the meat that might be near the bone, but do you mind helping a feller out by tell me at what part of the 139 pages of that post should I start reading?
I'm thinking it's the last line of his post where he says the contents of his homemade lube.

I think if you are looking for a combination of both jacketed bullet velocity AND accuracy, the only way to do it is with paper patched.
 

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I don't mind chewing on some of the fat to get to the meat that might be near the bone, but do you mind helping a feller out by tell me at what part of the 139 pages of that post should I start reading?
I studied the whole thread. There is no magic formula. Everyone's particular situation dictates their own needs. Based upon the fact that the upper that I had built by ARP was particularly smooth from the get go, I am able to escape (relatively speaking) lead fouling issues at higher velocities. My initial needs were specific to the 444S and 10mm Delta Elite.
I was having serious wax blow-by in the 10mm auto. I was having failure to lock into battery after two mags. This started to occur at temps above 75 F. I needed a lube that would hold up at higher temps. Cold bore 1st shots in my 6.8 were another concern. After researching the Ultimate Lube Quest thread, I built "one" of the formulas mentioned. It totally cured my issues with the 10mm auto. It also helped with my accuracy issues in the 444S. I'm pushing a ~260 gr. Keith style boolit (Lyman #429244)to 2300 fps. 1.5" group at 100 yds. Initially my spread was in excess of 3". Cold bore shots are now acceptable for hunting within 200 yds.
I highly recommend that one spend the time researching the WHOLE thread to find what may work for YOU. As jameslovesjammie noted, my formula is noted in my last post. You have to read the thread to learn the techniques to build it though. Cannot just dump the ingredients together. The soap melts at or near 450 degree F. Beeswax is melted into the mix at cooler temps. I will try to find the specific safety instructions and post them later. Gotta go work...
 

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Lots of work, most likely still need a gas check. I am thinking of powder coating for 6.8. Still need a gas check, but you coat and bake, then size. The Hi-Tek requires multiple lubings and bakings, then sizing.

Don't get me wrong, it's good stuff. When properly applied to a bullet, you can smash it flat as a nickel and it won't chip or peel off. But properly applied is the key. There is a 100+ page thread on castboolits about it.
 

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I am also interested in cast boolits for the 6.8mm…

I have shot the 280642 (~150 grains) just as a means of fire forming the brass to the chamber of the T/C 23” Carbine barrel…

I was getting misfires so I used the 280642 seated long to allow it to contact the rifling and keep the case from being pushed forward during primer strike—this was causing misfires…

Just out of curiosity, I shot 10 of them at 75 yards using Trail Boss powder—a moderate charge for 1013 fps...

The group is shown on the attachment. Not bad for just using it to fire form cases…

The problem is that the impact point is much to low to use it concurrently with the 90 HP Sierra bullet. Too much ‘scope adjustment and that I am not into…

I have some 130’s on the way from a person on another site—but it has been a bit longer than I thought it was going to be…

I have sized the 287346 down to 0.278” but the bore riding area on the boolit requires the seating depth be way far below the neck/shoulder junction—I don’t think that will work well…

Hopefully the light cast boolits will be the ticket—if I get them…

I’ll follow this thread as that is really what I want my T/C Carbine to shoot—cast…

Good-luck…BCB
 

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Sorry for the necro post, but there are so few current posts on cast 6.8 spc. I took a cheap 135g lee 2 cavity and milled it off down to the gas check shoulder. I Powder Coat all my cast, so the Gas Check is unnecessary. The resulting bullet weighs 120g, and the driving bands are a perfect match for the 6.8 case neck length. Also, the bore riding nose shape is a perfect fit inside the land to land dimension of the barrel. The loads shoot great in my 16" AR at 2300 fps.
 

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Has anyone powdercoated 6.8 projectiles and tried them? I know a lot of coaters say not to push them past 2200fps to keep from leading the bore.
 

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I’m currently working on cast subsonics for my 6.8. Custom mold for 214gr Bullets. Planning on pc but having trouble with the bullets bending after sizing. Shot some unsized yesterday with good results other than not enough powder to cycle the action. I’ll keep tweaking it. It was only a function test on the new ar build I completed. My normal plinking load cycled perfectly.


Sent from my iPhone using Tapatalk
 

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My cast load for 6.8 is-

Lee 135gr RF GC @ 19Bhn.
(lapped oversized)
Sized .278"/Lubed/Gas Checked/Sealed
taper crimped to remove case mouth flare
StarLine/CCI 400
Alliant Pwr Pro Varmint @ 31.0gr
2.235 OAL
2450 fps thru Oehler 35P

Liberty 18" mid gas 1:11" twist
Superlative adj gas block
Sprinco red carbine spring
Oden hvy 5.3oz carbine buffer

several hundred fired to date w/o issues.
 
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