280468S, 5.0gr Unique, 6.8 Remington SPC

[ohland]

After lots of hem-hawing and advanced diddling, I went to the range with my 6.8 and cast boolits. Not sure of the hammer spring strength and the hammer extension (added weight makes weak springs even more of a problem) on the G1 Contender. I had two complete FTF (four plus tries) plus one more misfire. BUT...

280468S boolits, w/GC, sized to .278 (oops, too much 7mm on my mind!)
5.0gr Unique
CCI 200 LRP
COL is as long as it can be. These have the GC about half in the neck. I wonder about the full length 280468, since I went through about 20 or so 285129 which are too long to fit the GC in the neck on my 7-30 Waters.

Attachment 111950

There are FIVE boolits in there. 25 yards, varying light winds from R-L . 3x-9x scope at 9x. The reason the group is low and right is that the Leopold scope totally ran out of elevation...

Attachment 111951

Ten boolits. My dad wanted things in the black, so I held on the number 7 with the lower vertical crosshair in the duplex, and placed the cross-hairs on the outer ring at roughly 10:30.

[FLHTC]

I have a line on an Encore barrel in 6.8 Remington but I hate the fact that the parent case is the 30 Remington. I have been on the fence with this barrel for weeks now and I can't seem to pull the trigger because of the brass. Have you found a good supply of it?

[ohland]

I have a line on an Encore barrel in 6.8 Remington but I hate the fact that the parent case is the 30 Remington. I have been on the fence with this barrel for weeks now and I can't seem to pull the trigger because of the brass. Have you found a good supply of it?

Hmm, parent case usually refers to forming it. You do want actual 6.8mm SPC brass?

Oops, I now remember seeing "30 Rem" brass, BUT don't forget that if it is "30 AR" from Remington that is a different case head (.473?).

Too bad it's in an Encore, the Contender 23" bull barrel is nice..

In the words immortalized in Apocalypse Now - "Do you want to surf, or do you want to fight? I'll surf, Sir!

Midway has Hornady and Remington.
Graf has Hornady.
Midsouth has Hornady and a 1,000 count box of Remington... whooo-boy!

[FLHTC]

Hmm, parent case usually refers to forming it. You do want actual 6.8mm SPC brass?

Too bad it's in an Encore, the Contender 23" bull barrel is nice..

In the words immortalized in Apocalypse Now - "Do you want to surf, or do you want to fight? I'll surf, Sir!

Midway has Hornady and Remington.
Graf has Hornady.
Midsouth has Hornady and a 1,000 count box of Remington... whooo-boy!

Yes, the 30 Remington is the parent case of the 6.8 Remington and if production of brass stops, so does shooting. That's why i can't bring myself to buy it.

[autofix4u]

Find a local Smith to cut your barrel for the rim, and 30-30 brass makes a fine replacement for the 6.8spc. Short trip through the fl sizer and trim to length. Then you have a 6.8spc rimmed. We all know that break actions prefer rimmed cases.

[ohland]

Find a local Smith to cut your barrel for the rim, and 30-30 brass makes a fine replacement for the 6.8spc. Short trip through the fl sizer and trim to length. Then you have a 6.8spc rimmed. We all know that break actions prefer rimmed cases.

If you are going to do the rim, please report back to the collective on how well it works. Although the Contender handles rimless cases well, once you use a rimmed case, it feels a bit crude with the rimless case having to push the extractor down. Yes, you will need the extractor for rimmed cases, but that requires no further parts. Just don't loose the darned roll pin....

Uh, a .25/35 but based on the 6.8 sized case. Now that would be interesting.

[wcavasos]

It sounds like you are pushing a .285 sized bullet through a .277 groove diameter barrel. Is this correct? Are you experiencing any pressure signs? It seems like that would be quite the squeeze. Is this normal? I thought .004-.005 over groove diameter would be pushing the limits. With the normal range being about .002 over.

[ohland]

It sounds like you are pushing a .285 sized bullet through a .277 groove diameter barrel.

This is a multipart answer, stay with me...

First, I was fantasizing over the 285448 for my 7-30, and I mistakenly had the sized diameter for the 7mm in the first post. My error.

I shot some 285129 boolits in my 7-30 Waters, they have the GC below the neck, yet there was no appreciable leading. The 6.8 has a short leade and unless you get something on the lines of the 104gr 280468 (S) the GC will be below the neck. BUT... my experience with the 285129/7-30 suggests with moderate loads, the plunging GC of the 125 gr 280468 (L) isn't a significant issue.

Yesterday I mic'd some as-cast 280468 and they came out as .282 [ed. error! the seam added about .003], no foolin. I have been sizing them down to the standard .278, but recent experience with sizing an "as-cast" .325 diameter 321297 with a .323 sizer for a 32-40 with a .321 bore makes me open to .003-.005. Boolits seem to shoot well, and if I had better sights, I would tell you how much better. Look at the molds for .277/270 boolits, the "280" stands for the "size-to" diameter, not the as-cast diameter.

I expect to pick up a .280 H&I die tomorrow to test this. Look at the 4th Ed Lyman Cast Boolit Handbook (or whatever). 270 Winchester "size-to" is .277 or .278, but .003 over bore diameter should be feasible.

The issue of what happens when sizing a boolit comes to mind. The bands widen, but the boolit also lengthens. Maybe if I size to a wider diameter, the boolit will lengthen less.

[wcavasos]

OK, that makes a whole lot more sense. There is a 6.8 SPC group buy on the NOE forum you might think about getting in on. It looks to be a dandy! But I could see the utility of using one mold for two different calibers. I have a 270-130-FN mold from RCBS that makes great 1000-1150 FPS rabbit killin rounds. But RCBS molds are $$$$ for so few cavities. Never again will I buy one of those heavy two cavity molds.

[ohland]

OK, that makes a whole lot more sense. There is a 6.8 SPC group buy on the NOE forum you might think about getting in on. It looks to be a dandy!

I want to know what the COL with the T/C chamber would be before dropping more $$$ on a mold. Besides, I spent the $$$ to get the 104 grain, might as well use it...

The RCBS molds that I have cast well. True, a bit heavy, but if you could cast with my 357-180-SIL, you would have a desire to own one.

[Harter66]

Here ya go 30-30,32Rem ,7x6.8 w/287-150,27-130PP,Serria 120 SP.
Attachment 112423

Goodsteel helped me some by which I really mean ,thist wouldn't exist w/o him. Any way,I used 6.8 data and have loaded several different bullets from 120 tho 175 gr in this . It was sort of a struggle to get it to go sub-sonic which happened w/the 287-150 (hunter) from NOE over 3.5 Unique. 22.0 RL10x is a nominal J load for 130gr so it was a place to start in the bolt gun. The 120 Serria clocked 2230 w/that load in Rem LRP brass w/CCI std LRP while w/no changes the 27-130 FP PP'd at 135gr clocked 2250 and shot groups just like this.
Attachment 112429
5 shots the 5th shot was operator error and thrown away.
Attachment 112433
Another shooting set while trying to get the sights and brand new build to talking.

For a down side w/the std 7mm twist rates compatable w/175 J sptzers, every Loverin bullet I've tried has tumbled throughout the load ranges. But thats just 1 guy w/a fast twist bbl at 4200' above sea level in a sub 25% humidity environment. The slower 10-14 twist bbls of the 27s should fair better.