Help with Herters 303 Brit dies,Please

[jb12k]

I have never reloaded 303 before, and I bought these dies off ebay. They appear to be new. I have removed the decapper pin, as I use a universal decapper. As you can see if the pics work properly, both dies have inserts. I am needing to know how to adjust these on both. Have never seen a neck sizing die, but don't think this is one, as there is really no adjustment other than how deep the decapper shaft goes in. Suspect it is some kind of universal body with an insert for 303(clearly marked insert). The seater die has a window in it ! Also has an insert marked 303 Brit. Insert moves freely when round is run into it, until it meets the seeter, which is adjustable for depth. The insert allows the bullet to almost completely enter it Any advise on these ? Just set up and use as normal dies ? Probably much angst about nothing, but better to ask here first for the experts advice-Thanks-jb12k

[jcadwell]

You WANT to necksize 303 to prolong case life... If the die is a full length, smoke the case with a match at the neck and shoulder. Then screw the die down in increments until you are sizing the neck, and just BARELY touching the shoulder. The soot on the case indicates what is being sized. So when the soot on the shoulder is rubbed a little, you know it is sized far enough. That will likely be about 3/4 of the neck sized down, which is fine.

If the die is a neck sizing die, screw it down to the base plate and back it off about a half turn. A neck sizing die is adjusted by raising or lowering the die, and locking it down with the jam nut. The only real difference is that die is cut larger than a full length die so it won't size the body of the case.

The windowed seating die holds the bullet as precisely vertically as possible. Set it up normally. Check and see if the die has a crimping feature in it, and adjust the die to provide the crimp you desire by adjusting the height of the die body. Then adjust the seating depth with the screw adjustment on the top.

Hope this makes sense. I've got some Redding 303 dies for my Enfield. Your dies are a cut above.

Good luck.

[JBMauser]

Your sizing die has a very good chance of being a neck only sizer but Herters made insert sleeves in both full length and neck size only. the sleeve will have some movement or slip as that is the way the die is made. Your only way to check is to take a fired case, lube it fully and lightly and run it up full into the die so the shell holder cams over on the base. take the case out and measure the body against another unsized case to see if the body was reduced. the window on the seater allows you to verify a straight up bullet. In some cases you can insert the bullet from above and run the case up to seat. The whole idea is for that moving sleeve to capture the bullet and maintain proper allignment for seating. These were Herter's premium dies. Best of luck. JB

[Firebird]

The windowed seating dies that I have heard of use the window to insert the bullet into the die. The die holds the bullet in alignment as the case is raised into the die. Should produce nearly zero runout instead of more usual .002" and up.

[jb12k]

Thanks Guys-It is full length, so I need to get a neck sizer. Otherwise looks like these will do nicely ! Thanks Again-JB

[jcadwell]

Use the full length die as a neck sizer. Works great. Screw it down just enough to size most of the neck, without touching the shoulders or body of the case.

[versifier]

Here's an idea that has worked out for me when deciding if I wanted to invest in a .223 neck sizing die (back before Lee came out with their collet dies, which I might add, you should seriously consider). I looked at my .38/.357mag dies and the little light came on. Using some fired cases, I backed off the sizer until it hit the neck just enough, and I measured the gap between the die lock ring and the top of the press with feeler gauge. Then I had a friend turn a spacer bushing on his lathe for me, but you could do it by hand with a fender washer and a wide flat file. It worked great, and saved me the time and hassle of readjusting the die every time I wanted to do one job or the other. I bought the neck size die anyway and passed the spacer on to another friend who wanted to see if he could get away with neck sizing for his Mini14 (he couldn't, too bad) and he passed it along in turn. I have no idea where it is now, but after 20+ years it has likely done some traveling.

[dragonrider]

Versifier's idea is a good one, to expand it a little if you made the washer as a "U" shape, that is cut off one side. you would not have to remove the die in order to install the washer, just back it off a couple turns insert the washer and retighten.

[jb12k]

Thanks for the tips, guys-I will give them a try !