GC which do you prefer?

[fanner 50]

I installed some Hornady GC on my 452/ 325Gr Lee bullets last night. I used my Lyman 4500. They seem to fit very loose. Is there a problem? The boolits are sharp and filled the mold well. Is there a better GC. I've seen threds that mention crimped GC's???

[chunkum]

Describe what you mean by "loose". Can you pull them off after seating them? Or just twist them on the bases of the bullets? In either event, a bit of "spring back" in the checks may be responsible and annealing your checks should help. As far as I know, all checks in current production are of the "crimp-on" type.
Best Regards,
chunkum

[fanner 50]

They can be twisted and a few came off in the lube process. Going to try casting this evening without release agent and see if there is a differance. Makes sence that if the release agent has any thickness at all it would diminish the size of the base.

[Lloyd Smale]

You can get a small lot to lot variation in gas check size and even mold size as far as the gas check shank goes. Some molds may prefer a lyman check but the bad news is there no longer any different then the horandys and good news is even if the lymans fit better they didnt crimp so your stroked either way. Last batch of gator 45s were a tad on the big side for me too. I talked to felix about that and he said that there going to vary a smidge depending on what larry buys for copper stock. Worse case senerio your going to have some fall off in flight which is a bad thing but the good news is that it wont effect accuarcy at 25 yards bad news is that it probably will out at a 100 yards. All the lymans used to fall off so your in no worse shape then we were 15 years ago. You could try annealing them as they may stay on better for you that way but in the testing i did it didnt help much. They seemed to hold a little better but some still came off. Best bet is to open up your gas check shank in your mold a tad.

[chunkum]

Will the gas checks go over the gas check shank (the bullet base) with just finger pressure? It sounds to me as if either 1) the gas check shank of the bullet is too small, or 2) they aren't being seated during the sizing operation. If the latter is the case, then a Lyman gas check seater might be helpful.
c.

[fanner 50]

Using a lyman gas check seater now. The GC's can be put on by hand easily. I ran 60 through the seater then lubed. Only 3 came off but I noticed that they were all loose enough to turn them by hand. It sounds like I need to open up the mold a little in the shank area. First I'll try the no release agent to see if that makes a dif. It appears that a few thousands would make a dif.

[chunkum]

In the larger calibers (say 0.401 and above) since lead or bullet alloy has practically zero "memory" or spring back and the copper of the gas check does have some spring back, this difference between the metals makes more of a difference in how tight the checks hold on after sizing. The larger dimensions make the degree of the spring back larger. So annealing (i.e. making softer by heating and allowing room temperature cooling), while not a cure for an undersized gas check shank, should, theoretically anyway, result in less springback of the copper check and tighter fit after sizing. However, if you are verrrrrrrrryy careful, the aluminum blocks of your Lee mould are much more amendable to cautious polishing with a very light abrasive in the area of the shank and, if you don't overdo it, you can improve things that way. I would serously doubt if the release compound has anything at all to do with the difficulty you're having.
c.

[Lloyd Smale]

I dont use a release agent. Anything in that mold other then lead is taking up space the lead is suppose to.