What's the history behind the moderator?

[okie]

What was the actual line of reasoning behind the moderators on the early carbines? I get that they help with cycling, but why didn't they just 86 the moderator and replace it with an equal amount of additional barrel length? I'm also not clear on why they were necessary in the first place. Our 10 inch carbines work just fine today, and I'm not seeing any obvious reasons why they shouldn't have worked just as well sans moderator back then.

[TomMcC]

I could be wrong here, but I read somewhere (Blackrifle book?) that it was used to cut the muzzle blast down to a 20" rifle. I don't remember reading that they did it to make it cycle properly. It's been years since I've looked into any of this, so again I could be off base here.

[BWT]

Part of it had to do with muzzle report as well. As far as make it sound more like an AK.

That’s what been said all over the inter webs anyway.

ETA: Which I always thought was funny.

To me all firearm reports sound very similar. Especially at distance.

If it were a machine gun and shooting full auto - I could so cyclic rate being an indicator. But, I don’t think that I remember that ever being cited. It was always that the gun report sounded more like an AK.

God Bless,

Brandon

[Eurodriver]

Part of it had to do with muzzle report as well. As far as make it sound more like an AK.

That’s what been said all over the inter webs anyway.

ETA: Which I always thought was funny.

To me all firearm reports sound very similar. Especially at distance.

If it were a machine gun and shooting full auto - I could so cyclic rate being an indicator. But, I don’t think that I remember that ever being cited. It was always that the gun report sounded more like an AK.

God Bless,

Brandon

Yeah I’ve been around guns all my life, even professionally, and from 1/2 mile away I wouldn’t be able to tell you if the gun was a bolt rifle or an AR15 or an AK.

Don’t want to drift the thread but I’d be curious if there are people who can. Hell I can barely tell the difference between a handgun and a rifle if it’s shot into a close berm. The only tell for me is loud magnum rifles or a sonic boom that last for 5 seconds (usually when a hunter misses a deer lol)

[markm]

why didn't they just 86 the moderator and replace it with an equal amount of additional barrel length?

Excellent question. Rob the cartridge of a bunch of velocity, but still have the additional length? Completely irrational.

[ABNAK]

Yeah I’ve been around guns all my life, even professionally, and from 1/2 mile away I wouldn’t be able to tell you if the gun was a bolt rifle or an AR15 or an AK.

Don’t want to drift the thread but I’d be curious if there are people who can. Hell I can barely tell the difference between a handgun and a rifle if it’s shot into a close berm. The only tell for me is loud magnum rifles or a sonic boom that last for 5 seconds (usually when a hunter misses a deer lol)

IIRC you were in Iraq, correct? I'll assume the distances were closer than 1/2 mile. Could you tell an AK at "combat distance"? I think in Vietnam the ranges were close in the jungle and maybe (?) it was more discernable from an M16. I've heard and read 'Nam vets saying that some guys would pick up an AK but you had to be careful because in that environment (i.e. not much of a clear line-of-sight) you could be mistaken for an NVA or VC and shot at by your fellow Americans.

[ABNAK]

Excellent question. Rob the cartridge of a bunch of velocity, but still have the additional length? Completely irrational.

True, but the comment about making the report like that of a 20" M16 I've heard before. Assuming that is fact, adding additional barrel length would help ballistics-wise but would indeed still sound louder than an M16.

Not sure if it was meant as a ruse to make the enemy think they were engaging a larger, better armed regular infantry unit as opposed to a six man LRRP or SOG team. I have read where some of those type of teams would load their first few mags with all tracers to make it appear that the enemy was engaging a larger unit. I guess every little bit of advantage in those life-or-death situations helps.

[turnburglar]

I think when they say "sound" more like an AK, they are looking at it from a total signature perspective. Think about it this way: the flash from a 11.5 AR would be pretty significant compared to a 16" AK. The longer and larger bore allows the AK to simply burn more powder. I also remember hearing that the actual moderators had baffles in them and would be classified as a NFA item by todays standards. The baffles and length of the device would give the short AR a more tame muzzle signature. In the jungles of 'Nam the SOG dudes would have been operating a lot in low light and no light. A short barrel AR would have very different signature from an AK in that kinda environment.

[1_click_off]

Googling after reading the posts above and came across this site. https://retrorifles.com/moderator-fl...ndo-1963-1974/ Looks like they have some neat gear and appears to be in stock.

[okie]

I think when they say "sound" more like an AK, they are looking at it from a total signature perspective. Think about it this way: the flash from a 11.5 AR would be pretty significant compared to a 16" AK. The longer and larger bore allows the AK to simply burn more powder. I also remember hearing that the actual moderators had baffles in them and would be classified as a NFA item by todays standards. The baffles and length of the device would give the short AR a more tame muzzle signature. In the jungles of 'Nam the SOG dudes would have been operating a lot in low light and no light. A short barrel AR would have very different signature from an AK in that kinda environment.

They have in recent history been reclassified as suppressors, but only because they barely fit the loose definition of one legally speaking. The sound reduction isn't appreciable, but since it's measurable, that's enough for the ATF to go after them. They have very little volume and no baffles whatsoever. Just a diffuser tube with several expansion chambers.

I don't know about the flash suppression, but I don't think they would be particularly effective at that either. Just guessing here, but I think that same length of additional barrel would be just as effective because it would allow more powder to burn. So I think in those terms it would be a draw between the 10 inch barrel with moderator and an M4. Contrary to popular belief, suppressors aren't all that great at flash suppression.

I am really surprised though that someone didn't say hey let's make this thing a little bigger and put real baffles in it. Actual suppressors of that length are very effective. I have a little k can on my Mk18 upper that does a really good job. It's not hearing safe by any means, but it's close. I've fired a few rounds without ear pro before to hear what it sounds like, and it was slightly uncomfortable, but not painful like it would be sans suppressor.