Lyman 4500 die retaining nut is....

[mroliver77]

I too use the ram to square the nut when starting it. My 450 must seal at the die bottom well because I shot a bullet through it yesterday and it came out completely lubed too! It has been setting a week or more and still had some pressure on the lube. I only "snug" the nut as it looks frail to me. My sizer had a problem with the lube leaking under it. After replacing the o ring and cleaning and fussing I realised that it had been machined at an angle to the bore(not 90 degrees). It had bent the pressure screw frome being off too. I epoxied the plate on the bottom of reservoir in and lapped the seat on the screw straight and it works great now. They are still way too wimpy for the job IMO. Jay

[454PB]

I make my own sizing dies for my 450 sizers. When I made the first ones, I machined the groove for the O-ring, but later learned that is unnecessary. As a side benefit of ignoring the O-ring, when I change dies the retaining nut is simply slipped over the top of the die. I then place the whole assembly in the sizer, place the wrench on the top as previously mentioned, and the nut starts easily. Some of the very stiff lubes available cause problems, but I just warm the top of the female threads with a blow dryer and things fit well.

[MARCORVET]

I broke one retaining nut on my 4500. Ordered a half-dozen to have a spare on hand. I realized that I broke the nut on a cold sizer. I now turn on the heater for at least 30 minutes before making a change (time consuming, but I usually continue casting while I am waiting). I have not had a problem with the nut since then. I barely snug the nut when installing it. Good Luck!

[dogdoc]

My 450s and newer 4500 work fine. I have no broken die retaining nut problems or exceesive leakage on any of them. You either have a bad set of nuts from a defective manufacturing run or something else is going on. The inherent design of lymans and RCBS's sizers are similar but I like the lyman better because of the ratchet on the pressure resevoir. I would call Lyman. My experience with their customer service was good. I think we here more negatives on these boards because dissatisfied people are more likely to report things than a satisfied customer is.

[pireaux059]

Hey yall new guy here, I have used a lyman 450 for years with no problem, I recently bought a rcbs in a ebay deal & it works equally well . I do like a previous poster stated & only snug the nut enough to hold the die in place. I have only had a problem once. I bungled some pieces on the 450, they sent the parts & instructions @ no charge. I have been a loyal customer since JD