I just found a box of Thermold magazines I bught years ago and never used. I’ve heard that some batches of these were worthless, but other were good to go. How to tell them apart: mfg dates, or some other code? Or are all Thermolds worthless?
If you PM me an address, I have at least 2 I’d send you for no charge.
I’m in California. No new Hi-caps for me!
Which is why I hope these ones are good.
move, dont you know california is one big earthquake away from being the lost state of california?
Shoot with 'em, duh!:rolleyes:
j/k I have no idea really.
How cold does it get where you are?
Up here most of us bought our own Al mags because the CF Thermolds were unmitigated crap.
I found one last winter while moving, took it out for a spin, 10 rounds later…
…I remembered why I crushed the rest years ago.
I don’t know about the US varieties, but if it has a maple leaf on it, it is crap, and it will break, hopefully not at a critical moment.
Krikey! What was the ambient temperature when the mag broke?
Look for “Thermold D&D INC WILSON NC” on the left side. “PAT NO. 4139959” is on the bottom, outside of floorplate.
PAT.NO 4139959
Abstract: An improved cartridge magazine constructed of high impact nylon resin and in which a spring urged follower pushes cartridges into a rifle into which the casing is inserted. The follower is attached to the spring which prevents fore and aft movement of the follower and the spring is curved to physically contact the bottommost portion of the follower to prevent the follower from pivoting about the spring contact. A removable floor plate is removably attached to the casing by means of a pair of resilient latches. The floor plate is symmetrical and has no preferred orientation, thereby simplifying loading of the cartridges.
Inventor Howard; William J. (P.O. Box 573, Wilson, NC 27893); Harvey; William A. (P.O. Box 3065, Wilson, NC 27893)
Owner/Assignee
Publication Date February 20, 1979
Application Number 796560
Filing Date May 13, 1977
US Classification 42/50
Int’l Classification F41C 025/02
Examiner Jordan; Charles T.
The US marketed Thermolds included the use of the Zytel material. “Zytel is a trademark owned by DuPont and used for a number of different high strength, abrasion and impact resistant thermoplastic polyamide formulations of the family more commonly known as nylon, often with varying degrees of fiberglass, from 13% to 60%, added in for additional stiffness”[1]. I had 50 of them and they never gave me fits. Sold them all to a guy in Guam when mags became available again.
[1]Wikipedia, “ZYTEL”
kingc, are you describing the worthless ones or the “good” ones?
Not so cold, maybe 15F or so.
They break in the summer too, just not as constantly.
The CF issued thermolds when the C7 was adopted until about 1992. They were a disaster.
I’ve heard in conversation that other/later thermolds were better, I have no desire to know any more. USGI mags don’t break into little pieces while being inserted on a closed bolt.
They do look good in pics though.
The “good” ones…
I broke 3 CF thermolds in a row in a training session within the first 60 rounds. The US ones without the Maple Leaf seems to work fine though.
The US ones marked D&D INC WILSON NC are okay, the ones made for the Canadian Military with the Maple Leaf suck.
I have used the US D&D ones before and they are okay. Great training mags. One thing I have seen several times at different classes and in LE training is that the bottoms of the mags will pop off if you drop them on concrete. If your going to use them get some mag pulls on the bottom of them and run the mag pulls front to back not side to side to protect the base plates.
Mine are marked D&D Inc.
“Great training mags”…so, does that imply that they are not for serious use?
CF issues the Thermold until 1995 (ish) depending what unit you where in.
Going to Rwanda we where issued the first batches of “metal” mags - the black Labelle Teflon’s
Later variants of the Thermold where better (they are date coded) – but they gave me a phobia about polymer mags I have only recently started to get over (with Magpul’s PMag).
Even the US made ones have bad luck in the cold.
“Great training mags”…so, does that imply that they are not for serious use?
I only use mine for training as I do not have a great deal of confidence in them. Since your in CA just use them for training / range trips and save your USGI’s for serious use. If you have some worn out USGI’s get some replacement bodies from CProducts.
- I stand corrected. I was trying to remember which mags I wasn’t allowed to own any more when the laws changed.
‘metal mags’, i remember the term.
FWIW, the broken one in the pic was an 89.
Regards,
Walt
Doesnt need to be hot or cold for that to happen. Thermolds are crap.
This has been my experience as well with 5 of the U.S. Made Thermolds. Each has around 1,000 rounds on it with no problems…but I’ve never shot them in “Arctic Chilled” environments.
I was always told that the "Canadian Made Thermolds
were the ones to stay away from. Regardless…I only use them for training.
Tack