Other direct impingment rifles?
- Thread starter SPUSCG
- Start date
the m16 family is the most prolific but it wasn't the first. just might be the last though.
the concept is over 100 years old according to this and the first successful use of it was in 1940
http://en.wikipedia.org/wiki/Direct_impingement
the concept is over 100 years old according to this and the first successful use of it was in 1940
http://en.wikipedia.org/wiki/Direct_impingement
Other DI rifles? A few, Daewoo, Armalite AR180, AR10. But why bother developing one when you can buy the best directly from the US Government?
Liability? What liability?
Advantages? Lots. Fewer moving parts than gas piston designs, lighter, less material required for manufacturing, better accuracy due to lower vibration and fewer moving parts, ease of maintenance and repairs, higher cyclic rate of fire.
Heck, even the guys at the Pentagon can't find any advantages to gas piston systems, the advantage is all on the Internet.
Not that I'm a fan of DI, but until you can show me something better . . .
Yeah, that's why it hasn't been very successful. Or copied.
Liability? What liability?
Advantages? Lots. Fewer moving parts than gas piston designs, lighter, less material required for manufacturing, better accuracy due to lower vibration and fewer moving parts, ease of maintenance and repairs, higher cyclic rate of fire.
Heck, even the guys at the Pentagon can't find any advantages to gas piston systems, the advantage is all on the Internet.
Not that I'm a fan of DI, but until you can show me something better . . .
The Ljungman/Hakim Rifle was a very good DI rifle. Instead of venting into a largely enclosed action/bolt carrier the Ljungman effectively vents to the atmosphere after impinging on a small cavity in the bolt carrier. Unlike an AR the carbon buildup wipes right off easily as the gas vented expands and cools quite quickly.
I honestly like my Hakim more than my Garand.
I honestly like my Hakim more than my Garand.
Pinky Carruthers
New member
The AR 18 was designed after Armalite sold the patent rights to the Ar 15 to Colt, and was designed to not infringe on the Ar 15 patent. The AR 18 uses a short stroke piston and has been heavily copied (HK G36, Bushmaster ACR etc).
For DI there is the Ljungmann(original), French Mas 36 (I think thats the model number) and the Egyptian Hakim.
The MAS-36 is a bolt action rifle 
.
The AR-18 is NOT DI.
The Daewoo K2 is NOT DI.
The AR-10 is DI.
The Ljungman/Hakim are DI.
The MAS-49 and 49/51 are DI.
The Rasheed is DI.
The Daewoo K1 is DI.
Am I the only one here who has google? Sheesh.
Really? Then what about M249, M14, and M27 IAR?
.The AR-18 is NOT DI.
The Daewoo K2 is NOT DI.
The AR-10 is DI.
The Ljungman/Hakim are DI.
The MAS-49 and 49/51 are DI.
The Rasheed is DI.
The Daewoo K1 is DI.
Am I the only one here who has google? Sheesh.
Really? Then what about M249, M14, and M27 IAR?
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Evil Monkey
New member
lol internet people still are complaining about DI vs piston.
One the subject of DI, the only TRUE DI rifles that I know of is the M16 family and the Daewoo K1. Both of these designs use the rear of the bolt body as a piston. The other rifles mentioned do not use the bolt body as a piston and therefore cannot be considered true DI rifles.
The other rifles like the mas49 and egyption rashid use a female carrier that connects to a male gas tube extension. The male extension acts as a stationary piston. lol
One the subject of DI, the only TRUE DI rifles that I know of is the M16 family and the Daewoo K1. Both of these designs use the rear of the bolt body as a piston. The other rifles mentioned do not use the bolt body as a piston and therefore cannot be considered true DI rifles.
The other rifles like the mas49 and egyption rashid use a female carrier that connects to a male gas tube extension. The male extension acts as a stationary piston. lol
Scorch, I know you are, and I am a fan of DI, it allows me to afford to purchase a military style rifle. All of the piston designs are beyound what I can afford. I know I could do a conversion kit, but why should I. The DI system works, does what I need and everyone should clean their rifle DI or not, semi or bolt.
What get's me is the argument on is my hammer better than your hammer, who cares?
Jim
chris in va
New member
They're certainly lighter, that's for sure. I compared $800 DI's with piston designs and guess which one was two pounds more?
Ummmm, OK, you say to the effect that the Ljungman type DI system really isn't DI because it uses the carrier as a moving cylinder and the AR series is DI because it uses the carrier as a moving cylinder.
You then try to differentiate this by word-smiting about the "piston" being the rear of the bolt, AR, vs the gas tube itself, Ljungman, trying to conclue that these are both vastly different methods of operation. This is like arguing that a 1972 VW Beetle and a 1983 Ford Ranger aren't both rear wheel drive vehicles because one has the engine in the front and one in the rear.
Pinky Carruthers
New member
My bad, it was the MAS 49 I was thinking of. Thanks Kozak.
Before the lock...
The DI is a great design for some uses. However, there are no new military designs using the concept - and there is probably good reason for it.
But, I can't buy a new machine gun, so the DI is fine for me. I also have plenty of time and a good place to clean my rifles.
-tINY
Not a huge fan of the M16/AR15 rifles....
And DI is a decent system, when done right, there's nothing wrong with it. Same goes for gas piston systems, too, IMHO.
However, there are many different designs, some do things better than others, for certain applications.
I never cared much for the specifics of the AR system, where the gas is vented inside a (mostly) closed receiver, and baked on. AR rifles are a huge PITA to clean. But they do work.
What makes a DI or piston gun interesting to the military is more than just the class of operation, it is how it is executed, and how much it costs. And the military procurement people (when not overrulled by politics) are seldom about the absolute best, more about "good enough" and "within budget."
And DI is a decent system, when done right, there's nothing wrong with it. Same goes for gas piston systems, too, IMHO.
However, there are many different designs, some do things better than others, for certain applications.
I never cared much for the specifics of the AR system, where the gas is vented inside a (mostly) closed receiver, and baked on. AR rifles are a huge PITA to clean. But they do work.
What makes a DI or piston gun interesting to the military is more than just the class of operation, it is how it is executed, and how much it costs. And the military procurement people (when not overrulled by politics) are seldom about the absolute best, more about "good enough" and "within budget."
Amen to 44 AMP
I like my DI system. Until Gas piston cost about the same I probably wont waste my time with one.
This is what finally convinced me to order my BCM upper.
http://www.bravocompanymfg.com/v/vspfiles/assets/images/filthy14_oct10.pdf
I think I saw a report that its over 40,000 rounds now.
I like my DI system. Until Gas piston cost about the same I probably wont waste my time with one.
This is what finally convinced me to order my BCM upper.
http://www.bravocompanymfg.com/v/vspfiles/assets/images/filthy14_oct10.pdf
I think I saw a report that its over 40,000 rounds now.
Bartholomew Roberts
Moderator
I keep seeing the "there are no new designs using DI" argument; but actually there are several new designs using DI submitted for recent military rifle competitions. A new version of the M16 was submitted for the IAR competition. LMT submitted the MRP for the Ministry of Defence .308 rifle. And there are something like 6 new DI versions submitted in the M4 replacement trials.
Do all of those "new" DI designs look like a slightly tweaked M16 design? Yes they do; but then again look at all the successful piston entries of late: HK416 for the IAR, LWRC M6 in the M4 replacement trials, even SCAR and Robinson XCR look very AR15-like in their ergonomics and design. The M16 has a great design in its ergonomics and barrel extension. New rifles tend to copy what works whether they are DI or piston.
Everybody here considers the HK416 a new design; but apparently some do not consider the Knights SR16E3 a new design even though it modified the DI gas system of the M16 and uses both a new bolt and barrel extension.
There are lots of new DI designs out there.
Do all of those "new" DI designs look like a slightly tweaked M16 design? Yes they do; but then again look at all the successful piston entries of late: HK416 for the IAR, LWRC M6 in the M4 replacement trials, even SCAR and Robinson XCR look very AR15-like in their ergonomics and design. The M16 has a great design in its ergonomics and barrel extension. New rifles tend to copy what works whether they are DI or piston.
Everybody here considers the HK416 a new design; but apparently some do not consider the Knights SR16E3 a new design even though it modified the DI gas system of the M16 and uses both a new bolt and barrel extension.
There are lots of new DI designs out there.
It might be asked the other way around - why are there so many different piston gun designs, can't they get it right? After all, 9 million AR's seem to be pretty much good to go without needing a lot of tweaking and changing around.
The AR15/M16 stands out because the American public doesn't know much about firearms, it's history, or even bothers to look at what other countries use. And lots of former piston gun armies have switched to the M16 variants because Colt and others enjoy a 45 year head start on price competition.
DI is just ONE feature of the AR design - and a lot of other companies have slavishly copied other parts, right down to the straight mag well. The AR mag design isn't the best one out there, either. It's just market dominance that keeps it alive.
The ergonomic control layout, two pin takedown, easy bolt removal, stock options, flattop upper, and choice of intermediate caliber have been heavily copied. Most new designs use the barrel extension, too, that is specifically the reason for the light weight. It also allows the use of a polymer lower, and extruded aluminum railed upper in newer designs. The heavy machined receiver with bolt lug lockup and screwed in barrel is basically dead for the future in small arms design. No point to it, a curio and relic.
Of course, the biggest misunderstanding of DI vs. Piston is thinking DI doesn't have one. Look closer, it's in the bolt carrier right there, and actually functions in reverse - the bolt carrier is the cylinder and gets propelled directly back, not thru extra parts. The piston head is the bolt tail itself, with gas rings to prove it.
Just another piston gun, and doesn't really get any more residue than a piston on the barrel. It's just public misconception and ignorance that cloud the view. Understandable, the public aren't firearms designers, just users, like car owners or keyboards punchers posting in threads. No clue.
They specifically are not trained in technical matters, have degrees in mechanical engineering, or even understand how to install a doorknob at home. They don't even fix their own flats - literally remove the tire from the rim, patch, and reassemble. Again, no clue.
Helpless zombies ....
The AR15/M16 stands out because the American public doesn't know much about firearms, it's history, or even bothers to look at what other countries use. And lots of former piston gun armies have switched to the M16 variants because Colt and others enjoy a 45 year head start on price competition.
DI is just ONE feature of the AR design - and a lot of other companies have slavishly copied other parts, right down to the straight mag well. The AR mag design isn't the best one out there, either. It's just market dominance that keeps it alive.
The ergonomic control layout, two pin takedown, easy bolt removal, stock options, flattop upper, and choice of intermediate caliber have been heavily copied. Most new designs use the barrel extension, too, that is specifically the reason for the light weight. It also allows the use of a polymer lower, and extruded aluminum railed upper in newer designs. The heavy machined receiver with bolt lug lockup and screwed in barrel is basically dead for the future in small arms design. No point to it, a curio and relic.
Of course, the biggest misunderstanding of DI vs. Piston is thinking DI doesn't have one. Look closer, it's in the bolt carrier right there, and actually functions in reverse - the bolt carrier is the cylinder and gets propelled directly back, not thru extra parts. The piston head is the bolt tail itself, with gas rings to prove it.
Just another piston gun, and doesn't really get any more residue than a piston on the barrel. It's just public misconception and ignorance that cloud the view. Understandable, the public aren't firearms designers, just users, like car owners or keyboards punchers posting in threads. No clue.
They specifically are not trained in technical matters, have degrees in mechanical engineering, or even understand how to install a doorknob at home. They don't even fix their own flats - literally remove the tire from the rim, patch, and reassemble. Again, no clue.
Helpless zombies ....