5 replies to this topic

[dustbowldiablo]

Wondering if a 39 round is worth buying? I am new to the tommygun and have not heard much about this drum?

[deerslayer]

Overall cartridge length can be critical on these as the design of the rotor uses just a little bit of internal space. Long rounds can bind up inside. Merle has a jig to take off a fraction of an inch to help deal with that problem. The feed lips are weaker than L drums being simple stamped steel.

On the other hand they can run pretty smooth, and they generally are cheaper by half than an L drum.

Ask yourself why you want a drum, looks or extended full auto fun? If its the drum dump, get a L drum.

My 2 cents
Dan

[Ron A]

I have several 39 rd drums. The springs are different in each, but they work with semi 27, work sometimes with the 28 and almost never with the 21 on full auto. Could send to Merle for work, but can't see spending the money on 39 rd drums.

[SecondAmend]

The 39 round drum is the "ugly sibling" of the family.

[mp40]

Well, considering that the 39 rounder was made for a toy ("modelgun" as the Japanese call them) cap firing Thompson, the spring is tensioned specifically for reliability for this toy alone..The MGC (Model Gun Corporation) Thompson employs weak action springs due to the power levels of the relatively weak caps. Also, the bolt being constructed of Zinc, is fairly heavy, this caused the engineers at MGC to carefully balance the spring tension(s) to insure proper function this of course, includes the (MGC made) 39 round drum. When these drums are used in a real Thompson, the cyclic rate is of course faster and the rounds weigh a little more so, the MGC spring just can't keep-up with the demand. And, the drum was built using metric dimensions this of course, causes fitting problems. The cartridge "ramp" at the feed lips is weak and it can be bent out of shape too..

[JustMe]

OK now I'm confused the XL drum with my 1927A5 was made for a toy gun?