Ok lets discuss the 8mm XCB, I am going to start with the 8mm-06 as a start, I would love some geniuses input here.
Joshua
Ok lets discuss the 8mm XCB, I am going to start with the 8mm-06 as a start, I would love some geniuses input here.
Joshua
Actually, I like the idea myself. My preference would be the stock 8 Mauser case but with the neck length of the 30-30 for deep seating purposes. Why, because my barrel would have zero freebore with 3 degree total throat, and twist commensurate with the primary boolit shot. My primary boolit would be the RCBS 180, so my twist would be 16 with 3 to 7 lands, each 0.005 in height with a rounded junction to the groove at normal angle. ... felix
I don't know what you are really asking because your case selection is already designed very well. ... felix
felix
I just don't see what the 8mm XCB gives you that the 8X57 in a purpose built rifle wouldn't.
It gives a longer neck and a different throat. A customer reamer could do the same on an otherwise stock 8 x 57 case by moving the shoulder a touch.
Biggest trouble with a custom reamer is getting a sizer that works.
You will learn far more at the casting, loading, and shooting bench than you ever will at a computer bench.
Don't you use the same reamer on a blank die set that you use to do the chamber. I thought that was how you did it.
I would be happy with a 8mm-06 standard made, if it were to be changed I would like the shoulder set back .075 to make a longer neck. But that is if we HAVE to play with the cartridge.
Bonanza-Forster loves that kind of work. Send them the reamers. ... felix
felix
Ok, I just looked in my loading manual, the 8mm-06 will push a 220 gr bullet to 2500 fps. That is exactly the performance I am looking for.
Do we need to change the design or should we just call this good? I know an easy way to make a *slightly* longer neck is to use 270 brass.
You got the case size you want in the standard 06. Why not use it without "qualming" about it? Remember, a lead boolit will shoot faster than a condom, suggesting the 06 size is slightly large. Hence, the stock German case size, or the XCB size. Do your own extrapolations. ... felix
felix
I don't think it was a smart **** comment, I think Felix was saying to think about it and the realities become rather obvious.
If an 8 mm 06 does 2500 with a 220 jacketed and lead would go faster then Felix is telling you it is too much case. Go with a 8 x 57 or the XCB case to reduce powder capacity.
8 x 57 eliminates all troubles in case forming, dies, etc. the XCB gives a better neck design and throat but requires some case forming. It would allow a tighter neck, use a neck turner, and get more preside bullet alignment.
So, what do you want and what are you willing to do?
You will learn far more at the casting, loading, and shooting bench than you ever will at a computer bench.
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I am sorry for being nippy, and I openly apologize to Felix, as fas as case forming I enjoy that kind of thing, so I will go with a 30 XCB necked up with no further changes. That will allow all the speed necessary and will be a proven design.
Now Tim, is the reamer a removable pilot or fixed reamer? If removable is it possible to use it to make the 8 XCB?
Jesse Dresler in Oregon has done a short 8mm on a BR or 308 x 1.65 case ( can't remember the details) it was not any adbantage over a short 30 and was.abandoned.Roy Smith's 338 Manx on a 1.5"(or so) .473 head diameter case was a success and should be revived.
Your mother was a hamster, and your father smelt of elderberries
I think a 8mm-08 case with a 3006 length neck would be perfect for this. It should be way more efficient than a 8-06 Plus it would work on a short action. You could use 7x57, 8x57 brass if you have it. Or 3006 if you really want to do a lot of case work.
BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
BR | Bench Rest | M | Magnum | RN | Round Nose |
BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
GC | Gas Check |