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Been trying out the Lee collet neck sizing die kit and have a question.

I have a RCBS rock chucker press, the Lee instruction say to 'screw the die in until it touches the shell holder and then pull back the ram and then screw it in one more full turn'. 'But if you have a non Lee press then you need to turn the die two full turns'.

If I do this two turn instruction then I can just about push the bullet in by hand. I then need to add say another quarter turn or so and the bullet will then be tighter, tight enough that I cannot readily push it in by hand, BUT is this tight enough??? How do you check that the neck is sized sufficiently?? is there some measurement or rule for .303 or is it just play it be ear and if you cannot push the bullet in by hand then its good to go?? The bullets are .311

Oh and during all this the press does not toggle over centre of its travel as per the instructions.

Mike

Take the Lee instructions as being a general procedure.
Make sure the dies internals are clean and burr free. I "shine" the decapping rod with 1200 grade wet n dry and penetrating lube.
You may have realised that it is possible to alter the neck tension by screwing the die down further.
I also think the brass thickness will alter neck tension and ease of sizing.
I size so that if a bullet is seated and the loaded round is pushed,bullet first,against the edge of the bench the bullet stays put.
I have found that sizing with collet dies requires about the same force as loading pistol cals with carbide dies.
I like Lee collet dies and have a few sets.
HTH
Tony

Adjust the die so that the bullet will not push into the case by hand. Load a bullet into said sized case using seating die (no powder in case) and then push loaded round against loading bench to see if bullet can be pushed into case. Its all trial and error to get the neck tension correct. Different manufacture of cases and different 'lots' will all require the collet die to be readjusted.
It is highly unlikely that you will get the press to overcenter. I used a .303 Lee collet press in my Rockchucker for years but have now gone over to a RCBS neck sizing die. I find that I get better results and more uniform neck tension using the RCBS die. It is still a matter of trial to find the correct settting. If you are unsure that the tension is correct, use a full length die and compare neck tension.
Idealy you want about 2-3 thou of tension. This is easily measured using a vernier caliper. Measure diameter of bullet say .311'' then adjust die so that internal dimension of case neck is .308''. There should now be enough tension to hold bullet firmly. If you are not happy you can increase the tension or depending on bullet add a light crimp. Bullets need a canelure for that. Do not crimp un-canelured bullets like Match Kings as you will damage the bullet and destroy accuracy.

Whenever I'm resizing cases I always use a lube wax and always keep a bullet handy to offer to the sized case: it's rough science but at least I know at that point in the process that I have actually sized the neck and not simply stopped at the point of feeling resistance in the die.

And I think it's fair to add that if you're shoving your 303 through stripper clips into the ten-round mag where they're being shoved about by the recoil, you might want more neck tension to keep things steady than you might if you were loading for single feed shooting with rounds being handed from ammo box to loading ramp.

Have you thought about crimping your 303 rounds? I never crimp personally but some swear by it.

I would leave crimping to revolver, underlever and ammunition that is going to be thrown around a lot before being shot.

Crimping is an elastoplast for inconsistent bullet tension usually due to inconsistent case neck thickness.

The Lee collet die does a very good job of addressing the case neck thickness issue without trimming as it sizes from the inside out so to speak, the mandrels can be easily reduced in diameter slightly to increase the tension if necessary by spinning in a drill and applying an oiled piece of fine emery cloth, check the diameter often.

Case spring back can be uneven and contribute to uneven neck tension, then annealing is your friend.

dromia wrote:I would leave crimping to revolver, underlever and ammunition that is going to be thrown around a lot before being shot.

Crimping is an elastoplast for inconsistent bullet tension usually due to inconsistent case neck thickness.

The Lee collet die does a very good job of addressing the case neck thickness issue without trimming as it sizes from the inside out so to speak, the mandrels can be easily reduced in diameter slightly to increase the tension if necessary by spinning in a drill and applying an oiled piece of fine emery cloth, check the diameter often.

Case spring back can be uneven and contribute to uneven neck tension, then annealing is your friend.

wel put Adam

dromia wrote:I would leave crimping to revolver, underlever and ammunition that is going to be thrown around a lot before being shot.

Crimping is an elastoplast for inconsistent bullet tension usually due to inconsistent case neck thickness.

The Lee collet die does a very good job of addressing the case neck thickness issue without trimming as it sizes from the inside out so to speak, the mandrels can be easily reduced in diameter slightly to increase the tension if necessary by spinning in a drill and applying an oiled piece of fine emery cloth, check the diameter often.

Case spring back can be uneven and contribute to uneven neck tension, then annealing is your friend.

I'm not engaging in argument but I do think that "inconsistent case neck thickness" and milsurp brass are not exactly strangers, p'tickliarly in previously-fired configuration. I also think that if the op is a beginner, resizing mandrels might be a big ask just at a time when he should be building confidence in his reloading skills.

Anyway, as I say, I'm not arguing so it's really up to the op to decide which advice to follow.

Regardless of the ability of the handloader I still think crimping is an inappropriate route to follow, especially if a tyro then they should be learning correct procedures rather than being taken down reloading cul de sacs.

Just my view and it is up to the OP to place what value they may of what they read.

The Lee neck dies work but I have found them to be a faff on to set up. Once they are set up they work OK. Lee dies are made to work in Lee press,s one of the problems I have had especially with 7.62x54 Nagant dies when set up in my press the vent hole was covered up causing dimples in the case shoulder. Took me a little while to work out what was causing the problem.

If you are using a RCBS press and you are new to the dark art and are wanting to neck size you may be better of with a RCBS neck die. They are easier to use for a beginner.
(I am not saying they will do a better job don't want to start a cat fight just saying they are easier to use especially if you all ready have a RCBS press and are a novice.)

I am with Adam on the crimping issue.

The die seems easy enough to setup and install etc and a few practice runs seem fine but I just wondered if there was a 'standard' to go to in terms of tightness (sounds a bit rude!).

the .311 to .308 seems like a good shout.

MikeB