>303

[PTB]

I have a lee 312 160 on the way ,im cast it lyman 2 (if i remember what it was called)with some AR2207 ,starting load 20 or so and work up ,any idea with AR2206 H[smilie=s:
May even see what happens in the M17(T Rex):violin:LOL my baby

[63 Shiloh]

Have you slugged your bore mate?

.312" is on the small side for most .303's I have come across, I have a No.4 Longbranch that slugs at .314" and I use a .316" boolit.

\Personally, I have had no luck with AR2207 in my .303's, AR2208 (Varget) or AR2206-H have given me best results with full throttle cast boolit loads.

If you want to have some quiet plinking loads, I have had good results with Trail Boss and Unique.

So, to answer your question, as long as your cast boolit is lubed and sized at least .001-.002" over groove diameter, try starting with 38gn of AR2206-H with the 160gn boolit. This load has been very accurate and mild in a few of my SMLE's.

With your P-17 though, try a heavy boolit of 180gn-200gn or so and 40gn of AR2208, it is a bloody good combo.


Mike

[JeffinNZ]

I would suggest you get in touch with Jim at Cast Bullet Engineering and get a mould that is actually cut for .303 Brit. The Lee moulds are woefully undersized for the stated purpose.

[MBTcustom]

Seriously, slug your barrel and remember that you have to wrap shim stock around the slug if you have a 5 groove barrel. Be sure that the slug cleans up all the way around so you get true groove depth (if it doesn't, just smoosh the slug with a vice to increase the diameter, and do it over.) Be prepared for a less than perfect groove depth, My 303 slugged at .3195 and a .302 Gage pin was a perfect fit in the bore. They had a bad habit of cutting the rifling too deep. This is not a problem for cast boolits if you make sure that your boolits are at least .001 over the groove diameter. If you dont make that happen you will be plagued by leading and shoddy accuracy. The good news is that If you follow these steps, you can make one of those old beaters shoot like a dream.

[rintinglen]

Goodsteel speaks wisdom. I ended up using a 323=470 LYMAN sized at .320 in my old No.1 mk. III.

[1Shirt]

The fat lady sings and the fat boolit shoots best in most 303's. My smelly likes .315-316 best. Less than that it will tell you it dislikes smaller and leads.
1Shirt!:coffee:

[303Guy]

Last night I fired what was to be the testing boolit for our postal in my mint bore MLE actioned No4 barrelled 303 sporter. It leaded!:-(

Actually, that bore is so 'mint' it needs to be fire-lapped to get rid of the manufacturing roughness. I also need a fatter boolit to fit the throat even though the bore is .304/.312. (At least I think the groove is .312!?)

[JeffinNZ]

Here are CBE's most recent .303 bullets. I have the 315 175, 313 215, 315 240. They are shoot very well.

http://img.photobucket.com/albums/v505/JeffinNZ/Shooting%20stuff/303BritishNew2011.jpg

[Sloffie]

Question, why wrap shim stock around the slug? Is that to prevent leading?

[oneokie]

Question, why wrap shim stock around the slug? Is that to prevent leading?

The purpose of wrapping the shim stock around the boolit is to provide a round surface to measure with your common micrometer. As mentioned above, most LE's have 5 lands and grooves. It is very difficult if not impossible to get an accurate measurement with a micrometer. One has to have a V-block to place the measuring slug in to get an accurate diameter otherwise. (and the standard for that particular V-block.

The shim stock process is to measure the thickness of the shim stock, wrap the boolit and measure, then subtract 2 x the thickness of the shim stock to arrive at the diameter of the slug/boolit that you just forced through the barrel, which gives one an accurate groove diameter.

[wiljen]

V-block method works for 5 groove rifling too.

http://www.castpics.net/V-block.jpg

[Canuck Bob]

I measured my 5 groove at the throat. Sizing to the throat is common advice here. You can ignore the barrel groove dimension and fit to the throat. My LE No.5 has a tapered throat and will take 315-316 bullets. I measured carefully on the throat slug were the rifling just starts and got .314, close enough for me on groove dimension.

[Hip's Ax]

I use gage pins and a v anvil micrometer for odd numbered groove barrels. I bought the v anvil because I was concerned about the "mic from a land to a groove" then use the gage pin and do the arithmetic. After buying the v anvil and rechecking my numbers I got the exact same result. This was a 3 groove barrel, I would have to buy a different v anvil mic for a 5 groove. I like the shim stock idea, this forum never ceases to amaze me.

[303Guy]

This was a 3 groove barrel, ...What barrel would that be? There is/was a barrel maker here in NZ that made three-groove target barrels for a range of calibres.

[Hip's Ax]

1889 Schmidt Rubin. Wanting to recreate the original paper patched ammo is what led me to this site in 2005. Like it so much I never left. :)

[nicholst55]

What barrel would that be? There is/was a barrel maker here in NZ that made three-groove target barrels for a range of calibres.

A number of U.S. barrel-makers offer 3 and 5-groove barrels now, notably Lilja and Pac-Nor. They're supposed to shoot better, last longer, or some such drivel.

[Hip's Ax]

Benchmark offers a 2 groove. Alledgedly less grooves causes less bullet deformation (I am speaking to .22 LR, a greased lead projectile) and in slower than usual twists. I got one of these barrels mounted for a friend on his prone rifle and its a 16.5 twist rather then a 16. My good friend who smithed it had to grind a custom pilot for his Elliot reamer so that he was happy with the fit but man, does that barrel pound them into the x ring.