Reloading for 303 Brit.

[Geilt]

Is there anything special I should know before I start reloading for 303 British?

The Hornady manual states that the cases often need to be trimmed back after fire forming but not much else. I guess this is due to the rear locking bolt allowing more stretch in the neck.

I'm also wondering if there is much of a difference between the different types and diameter bullets (.311-.312"). I know the normal factory load uses a 150gr spitzer style bullet but do other styles such as a spire point or boat tail work well enough to try?

By the way, a while back I was asking for a recommendation on a reloading press. Being that I am just getting in to it I've decided to go with something along the lines of a Rock Chucker and take the money I would have spent on a higher end press and spend it on other reloading accessories. I can always buy the better press once I prove to myself that I'm sticking with reloading. I appreciate everyone's recommendations and I'll definitely go back and follow the advice offered a little while down the road.

[pigpen]

Hornady 180gr RNSP works pretty well in mine. I'd slug the barrel 1st & see if you need to get a pot & a .313 mould.

[WildBillCody]

174 gr shoot great in mine, I wish someone would make a SP in 174, neck size them only, they will last longer.

[Jacobite]

I neck size only to help prevent case stretching. I have used Sierra 180 grain round nose soft points and Hornaday 150 grain spire points with equal success in both my No.4 Mk1 and my Lithgow No1 Mk3. As for trimming, I keep an eye on every thing I reload and keep them trimmed to min. spec. I will add that I use loads that are closer to minimum velocity in my .303's

[pigpen]

I neck size only to help prevent case stretching. I will add that I use loads that are closer to minimum velocity in my .303's

I knew I forgot something, ^^^what he said^^^ Especially just for plink'in, keep the pressure low & you can get close to 5 loadings off of each case. At least I have. After 5 reloads, have that broken shell taker-outer handy, you'll probly need it.

[Geilt]

Hornady 180gr RNSP works pretty well in mine. I'd slug the barrel 1st & see if you need to get a pot & a .313 mould.

I already have plans to cast the chamber and slug the barrel this weekend. Never done it before but I've done my research. I'll probably take some pics of the process and put something together.

[Geilt]

I knew I forgot something, ^^^what he said^^^ Especially just for plink'in, keep the pressure low & you can get close to 5 loadings off of each case. At least I have. After 5 reloads, have that broken shell taker-outer handy, you'll probly need it.

Ouch. I hadn't thought about getting a shell extractor. I'll put it on my next list of purchases. THANKS!

[drhall762]

The .303 Brit headspaces of the rim. No secret. I have found that the chambers in my two rifles are a little long, so to speak. I have read some folks say this was done for reliability reasons, I don't know. I do know that if I full length size my brass, it sets the shoulder back and works the brass terribly.

If I neck size only, my brass lasts a long time. Reminds me of the Tootsie Roll comercial.

Don't know if this helps or not.

Dave :sniper:

[Geilt]

I just set the Cerrosafe in the chamber for casting and I'm waiting for it to cool for an hour before removing it. Once I have my measurements I'll recast it again for comparison and then move to slugging the barrel.

I tried using a lead dipper this time and it had already started to set in the few seconds it took to move from the pot I used to melt it to the chamber. If I try to use the dipper again I'll definitely bring it up to temp also. Hopefully that will keep it liquid enough to pour.

I'll post pics of the results after the second casting is removed.

[Geilt]

Of the two chamber castings, the second definitely came out better as I poured it faster. Both are accurate as the measurements match up exactly.

I also slugged the barrel but, uh, kinda lost the slug casting before I could take the picture.

Casting #1 is on the right, Casting #2 is on the left.

Measurements:
Neck = .351" on both
Chamber = .318" on both
Neck to Rifling = .22" on both
Barrel = .311"
Rim to Neck = 2.167"

[pigpen]

Nice moulds, never thought about doing that, sure would have saved me some time when I 1st started reloading for .303. If your barrel slugs @ .311 then those Hornady's ought to be pretty good. I have reloaded close to 300 of them they they all mesured .312. That should allow the lands to put a nice spin on'em.

[XO3319]

I've use Hornady 150gr Spitzers, 180 gr SPRN with IMR 4895, 3031 and 4064 with good results

I have about 300 174gr FMJ that I am itching to try in my BREN (when it comes) and in my Savage Number 1 Mk IV*

I full length resize and have had no problems using standard Large Rifle Primers (both winchester and CCI)