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How bad does the 37mm kick compared to a actual 40mm?
4/5/2010 1:07:20 AM
Im wondering specifically about how the recoil from a 37mm tear gas round would compare to a 40mm explosive shell. Is is way more recoil with a 40mm? I know its two completely diferent rounds, Im just curious about it. Thanks.
4/5/2010 12:25:46 PM
Recoil compared between 37mm gas, and 40mm HE or HEDP..... The 37mm uses black powder, normally 30-80 grains to propel a 1/2 lb projectile 50-150 meters semi accurately. The 40mm uses 330mg of M9 propellant to lob a 1/2 lb projectile 400 meters semi accurately usig a high/low pressure chamber system.
Easy answer is, the black powder offers more recoil based on the amount of black powder and the fact it does not use a "high/low" pressure launching system. The M118 casing, as used in the 40mm HE rounds uses a high pressure "chamber" that uses a very small amount of powder to chuck a grenade a good distance. The pressure developed in that chamber is 25,000 psi. Much more than developed in a 37mm casing. That pressure is "dumped" into the low pressure chamber (the inside of the casing) and reduces to 3000psi, which propels the grenade at around 250fps. The walls of the high pressure chamber are 1/4" thick, to hold that pressure. This results in much less felt recoil in the 40mm.
GROG
Easy answer is, the black powder offers more recoil based on the amount of black powder and the fact it does not use a "high/low" pressure launching system. The M118 casing, as used in the 40mm HE rounds uses a high pressure "chamber" that uses a very small amount of powder to chuck a grenade a good distance. The pressure developed in that chamber is 25,000 psi. Much more than developed in a 37mm casing. That pressure is "dumped" into the low pressure chamber (the inside of the casing) and reduces to 3000psi, which propels the grenade at around 250fps. The walls of the high pressure chamber are 1/4" thick, to hold that pressure. This results in much less felt recoil in the 40mm.
GROG
4/26/2010 3:46:24 PM
Grog, you didnt happen to be in tyler texas last week did you? I saw a guy in a red jeep liberty with a sticker of an m-79 on the back window and he looked just like you did in your video where you were testing the different rounds. 
4/26/2010 8:23:49 PM
My Liberty is Green, and rarely out of PA. Plus, the 79 in the rear window, is no "sticker". 
4/26/2010 8:25:28 PM
It has been 20 years, but I don't recall the M203 having much kick at all.
4/27/2010 7:19:50 AM
No, it doesn't. However they do make adapters today that can be used to fire all gauges of shotgun. I have everything from .410 to 10ga. I fired the 10 once. It worked. Other than that, it sits with my collection. I use the .410 the most, just for fun. I know the manufacturer of the 12ga-40mm adapter and she sends them to troops in the sandbox for use in combat. GROG
4/27/2010 7:34:27 AM
Originally Posted By DV8:
It has been 20 years, but I don't recall the M203 having much kick at all.
It has been 20 years, but I don't recall the M203 having much kick at all.
I agree - I remember a 203 off an M16A2 as about like a 12 gauge trap or skeet load I think. Not bad.
