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Quoted: We haven't seen much posted about this different and unique rifle. Yes, it's a piston but I say it's different and unique because Colt's approach to the parts is quite unusual. Rather than use a solid rod, Colt added a swivel joint. This joint allows the piston to "float" free of the rod. This, in theory at least, keeps the piston from adding any undue stress on the barrel when things start heating up. Here's the assembled rifle. Note that Colt used a built-in folding front sight rather than a railed gas block. Excess gas is vented out the small bleed-off hole located on both sides of the block. http://img.photobucket.com/albums/v221/tokarev/P1020010_zpse40fe559.jpg To access the piston, the small captured pin is pushed out as far as it will go. This allows the piston parts to be removed as a complete unit. Note the opposing grooves in the block. These help free the piston if it's frozen in place from carbon. Twisting the plug will cam it against these surfaces and help with removal. http://img.photobucket.com/albums/v221/tokarev/P1020007_zpse2430066.jpg The piston assembly removed from the rifle. http://img.photobucket.com/albums/v221/tokarev/P1010986_zps690bcb09.jpg The piston parts disassembled. http://img.photobucket.com/albums/v221/tokarev/P1010987_zpsab78bd58.jpg The transfer rod is attached to the piston by means of a small internal snap ring. The two parts are easily seperated by simply pulling them apart. http://img.photobucket.com/albums/v221/tokarev/P1010989_zps51515f87.jpg The piston. Note the three small gas rings. http://img.photobucket.com/albums/v221/tokarev/P1010990_zps8497dbc2.jpg The ball on the end of the transfer rod that works as the joint for the piston. http://img.photobucket.com/albums/v221/tokarev/P1010992_zps5f5ae048.jpg I'll take one please. |
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Pics of BCG? Can you also check the lockin lug recess for a extractor support? Also pics of the chamber... Sorry for asking for so mich.
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Pics of BCG? Can you also check the lockin lug recess for a extractor support? Also pics of the chamber... Sorry for asking for so mich. I'll see if I can't get some photos of the bolt carrier posted tomorrow. This rifle is the newer style with the one piece carrier. There is no extractor support in this rifle. As far as I know, that's something that only HK and SIG are doing. |
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Pics of BCG? Can you also check the lockin lug recess for a extractor support? Also pics of the chamber... Sorry for asking for so mich. I'll see if I can't get some photos of the bolt carrier posted tomorrow. This rifle is the newer style with the one piece carrier. There is no extractor support in this rifle. As far as I know, that's something that only HK and SIG are doing. Thanks. Wouldnt mind seein what extractor spring setup its running. Is it a standard DI bolt they are running? Does it still have the steel cam pin support in the upper? By far one of the most looked forward to rifles in the IC. This is probably one of the most testing piston rifles ever, given that it is an evolution from the 703, to the Type-C, then the M5, and now this. |
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Pics of BCG? Can you also check the lockin lug recess for a extractor support? Also pics of the chamber... Sorry for asking for so mich. I'll see if I can't get some photos of the bolt carrier posted tomorrow. This rifle is the newer style with the one piece carrier. There is no extractor support in this rifle. As far as I know, that's something that only HK and SIG are doing. Thanks. Wouldnt mind seein what extractor spring setup its running. Is it a standard DI bolt they are running? Does it still have the steel cam pin support in the upper? By far one of the most looked forward to rifles in the IC. This is probably one of the most testing piston rifles ever, given that it is an evolution from the 703, to the Type-C, then the M5, and now this. I've had the bolt out but haven't pulled the extractor to see if it has a black insert or something else. The bolt is standard GI stuff with the gas rings. The rifle came with an H2 buffer. And, yes, it still has the steel insert in the upper do prevent cam pin drag. I tend to agree that it's likely Colt has really done its homework with this gun. It will be interesting to see what the future holds for Colt and this design. |
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Pics of BCG? Can you also check the lockin lug recess for a extractor support? Also pics of the chamber... Sorry for asking for so mich. I'll see if I can't get some photos of the bolt carrier posted tomorrow. This rifle is the newer style with the one piece carrier. There is no extractor support in this rifle. As far as I know, that's something that only HK and SIG are doing. Thanks. Wouldnt mind seein what extractor spring setup its running. Is it a standard DI bolt they are running? Does it still have the steel cam pin support in the upper? By far one of the most looked forward to rifles in the IC. This is probably one of the most testing piston rifles ever, given that it is an evolution from the 703, to the Type-C, then the M5, and now this. I've had the bolt out but haven't pulled the extractor to see if it has a black insert or something else. The bolt is standard GI stuff with the gas rings. The rifle came with an H2 buffer. And, yes, it still has the steel insert in the upper do prevent cam pin drag. I tend to agree that it's likely Colt has really done its homework with this gun. It will be interesting to see what the future holds for Colt and this design. Im glad to see some actual pics of this rifle. You may be in posession of America next rifle. |
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Pics of BCG? Can you also check the lockin lug recess for a extractor support? Also pics of the chamber... Sorry for asking for so mich. BCG PICS please |
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I should be able to get some photos of the inside of the upper and the BCG tomorrow.
I didn't think anyone would want to see these since pics of the upper and BCG have already been posted elsewhere. Sorry for the oversight. |
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It is interesting to note that the newer DI 6940's also have the steel cam pins installed in the upper.
I presume that Colt does this to stock only one upper receiver part in inventory for the 6940/6940P's. Cost saving measure perhaps. One of my 6940's has the cam pin insert and the older one does not. |
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It is interesting to note that the newer DI 6940's also have the steel cam pins installed in the upper. I presume that Colt does this to stock only one upper receiver part in inventory for the 6940/6940P's. Cost saving measure. One of my 6940's has the cam pin insert and the older one does not. Cool. I did not know that. It certainly would make sense that Colt would be trying to limit the amount of parts it is making/stocking for all the variants in production. This makes me wonder if Colt will, at some point, offer a piston conversion as part of the 6940 package. |
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I doubt it.
The gas block ( and most likely the complete barrel assy), BCG, and of course, the piston assy will need to be replaced in order to accomplish this. In my mind its not cost effective. I know someone is going to stomp on my dick for saying this but I'm not convinced that the advantages of a piston rifle are worth what the upgrade of the above parts would cost. That being said, if I were to own a piston rifle it would be the 6940P. I'm a big fan of Colt 's monolithic upper receiver. |
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I doubt it. The gas block ( and most likely the complete barrel assy), BCG, and of course, the piston assy will need to be replaced in order to accomplish this. In my mind its not cost effective. I know someone is going to stomp on my dick for saying this but I'm not convinced that the advantages of a piston rifle are worth what the upgrade of the above parts would cost. That being said, if I were to own a piston rifle it would be the 6940P. I'm a big fan of Colt 's monolithic upper receiver. I think your right on track with this statement. |
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I doubt it. The gas block ( and most likely the complete barrel assy), BCG, and of course, the piston assy will need to be replaced in order to accomplish this. In my mind its not cost effective. I know someone is going to stomp on my dick for saying this but I'm not convinced that the advantages of a piston rifle are worth what the upgrade of the above parts would cost. That being said, if I were to own a piston rifle it would be the 6940P. I'm a big fan of Colt 's monolithic upper receiver. you are completely right piston offers no real advantage that justifies the extra parts, complexity and cost. Im not piston fan, but if I did lose my mind, it would be for the 40P several of those features are also on the 901. the rails on the rear of the bolt carrier for piston use, and a couple of other things are also on the LE901-S COlt plans to offer the 901 7.62 NATO carbine in a piston version eventually, But I wouldnt pass on a DI 901 waiting on it though if some one gets hot for a P901 after they read this |
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I doubt it. The gas block ( and most likely the complete barrel assy), BCG, and of course, the piston assy will need to be replaced in order to accomplish this. In my mind its not cost effective. I know someone is going to stomp on my dick for saying this but I'm not convinced that the advantages of a piston rifle are worth what the upgrade of the above parts would cost. That being said, if I were to own a piston rifle it would be the 6940P. I'm a big fan of Colt 's monolithic upper receiver. you are completely right piston offers no real advantage that justifies the extra parts, complexity and cost. Im not piston fan, but if I did lose my mind, it would be for the 40P several of those features are also on the 901. the rails on the rear of the bolt carrier for piston use, and a couple of other things are also on the LE901-S COlt plans to offer the 901 7.62 NATO carbine in a piston version eventually, But I wouldnt pass on a DI 901 waiting on it though if some one gets hot for a P901 after they read this I've had the hots for a 901 for awhile now. I wouldn't mind it being DI or piston. |
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Great pics Thanks Melvin!
Really nicely done piston system from the looks of things |
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I have been wanting one of these, is there a serial number range where the 1 piece carrier started? How does it shoot? Thanks for the pix
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Well, guys, I'm happy to say that I got the chance to fire the rifle this morning. Range time was limited and I didn't get to do all I wanted but I should have a good enough zero going that the rifle won't take too much tweaking when I finally do get it on paper.
Range work consisted of firing for "zero" on a 10” steel plate at 50 and 100 yards and then firing a few distance transition drills on these targets. After this, I stuck the upper on a select-fire lower and finished off the remainder of the first magazine by running a few 2- and 3-rd bursts. I finished off the morning with a 30rd full-auto mag dump. Overall, the gun feels smooth and really doesn't feel any different than a Colt 6920. No surprise there. On full-auto, the gun seems gassed appropriately and the cyclic felt and sounded about like it does with a DI gun. Total round count so far is only sixty rounds. Ammo used was Wolf 62gr FMJ. More to come.... |
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The newer one piece bolt carrier. There is no chrome lining to the interior of the carrier. http://img.photobucket.com/albums/v221/tokarev/P1020018_zps968d22f9.jpg Sir, Are you talking about the chrome lining on the inside of the carrier were the bolt gas rings make contact with the carrier and slide in & out? Because my LE6940P APC with one piece BCG is chromed lines inside the carrier where the bolt rings make contact with the carrier & slide in & out. On mine you could see the chrome lining without taking the bolt out just like a DI bolt. You can see the 1/8 chrome ring on the carrier face. When I took the bolt out & checked the chrome lining it was perfect! I did have a problem getting the bolt back in, It was REALLY tight!! Can you please clarify? |
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OP - Great pics and info! Many thanks! This thread alone has got me looking into the LE6940P, basically all I need is the upper as I have more than enuf lowers.
Question - I can't find any online info telling me if this monolithic upper uses standard barrels, barrel nut, or if there's something different. I don't know of another "true" monolithic upper/fore-end combined with a piston design AND using a standard off-the-shelf "mil-spec" barrel and barrel nut. (LMT's MRP for instance has proprietary barrels.) Sorry...don't mean to hijack the OP's thread...just wondering if someone knows. Thanks in advance! |
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OP - Great pics and info! Many thanks! This thread alone has got me looking into the LE6940P, basically all I need is the upper as I have more than enuf lowers. Question - I can't find any online info telling me if this monolithic upper uses standard barrels, barrel nut, or if there's something different. I don't know of another "true" monolithic upper/fore-end combined with a piston design AND using a standard off-the-shelf "mil-spec" barrel and barrel nut. (LMT's MRP for instance has proprietary barrels.) Sorry...don't mean to hijack the OP's thread...just wondering if someone knows. Thanks in advance! Not a standard barrel or barrel nut. |
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Saw one today at a local gunshop, $2795 plus tax, Nice, but not that nice.
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The newer one piece bolt carrier. There is no chrome lining to the interior of the carrier. http://img.photobucket.com/albums/v221/tokarev/P1020018_zps968d22f9.jpg Sir, Are you talking about the chrome lining on the inside of the carrier were the bolt gas rings make contact with the carrier and slide in & out? Because my LE6940P APC with one piece BCG is chromed lines inside the carrier where the bolt rings make contact with the carrier & slide in & out. On mine you could see the chrome lining without taking the bolt out just like a DI bolt. You can see the 1/8 chrome ring on the carrier face. When I took the bolt out & checked the chrome lining it was perfect! I did have a problem getting the bolt back in, It was REALLY tight!! Can you please clarify? Yep. The interior bore on the bolt carrier is not chromed on my rifle. The bolt is a standard GI part--to include gas rings--but there's no chromed surface anywhere on the bolt carrier. I'll see if I can't get a picture this afternoon. |
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Nice info Mel.
It is interesting that Colt can use the gas rings and the AA needs to use a spring and the removal of the gas rings. |
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Nope. No chrome here. I don't think any is needed since there aren't any hot gasses getting blown into the carrier. http://img.photobucket.com/albums/v221/tokarev/utf-8BSU1HLTIwMTMwMzAyLTAwMzQ5LmpwZw_zpscc0f4667.jpg Odd no chrome there. Double checked mine & it is definitely chrome lined. Anybody else have a colt LE6940P APC with one piece BCG. Chrome Lining or not? |
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Did you have trouble trying to reinstall the bolt?
Was it tight? Mine appears to have a socom profile barrel, how about yours? |
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Did you have trouble trying to reinstall the bolt? Was it tight? Mine appears to have a socom profile barrel, how about yours? The bolt fit is pretty snug just like it is on a nice new tight DI gun. Mine is the SOCOM barrel profile, too. |
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Did you have trouble trying to reinstall the bolt? Was it tight? Mine appears to have a socom profile barrel, how about yours? The bolt fit is pretty snug just like it is on a nice new tight DI gun. Mine is the SOCOM barrel profile, too. Thank you for your time. My bolt was tighter than normal. The fact that mine is chrome lined & yours is not is very odd. I guess the only thing consistent with colt is inconsistency. |
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Did you have trouble trying to reinstall the bolt? Was it tight? Mine appears to have a socom profile barrel, how about yours? The bolt fit is pretty snug just like it is on a nice new tight DI gun. Mine is the SOCOM barrel profile, too. Thank you for your time. My bolt was tighter than normal. The fact that mine is chrome lined & yours is not is very odd. I guess the only thing consistent with colt is inconsistency. It's more of an evolution to the platform, which is why there are different revisions out there. |
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Did you have trouble trying to reinstall the bolt? Was it tight? Mine appears to have a socom profile barrel, how about yours? The bolt fit is pretty snug just like it is on a nice new tight DI gun. Mine is the SOCOM barrel profile, too. Thank you for your time. My bolt was tighter than normal. The fact that mine is chrome lined & yours is not is very odd. I guess the only thing consistent with colt is inconsistency. It's more of an evolution to the platform, which is why there are different revisions out there. They are both the same one piece bcg. I understand the revision from the two piece bcg to the one the one piece bcg, but one one piece bcg chrome lined & another one piece bcg not? |
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Did you have trouble trying to reinstall the bolt? Was it tight? Mine appears to have a socom profile barrel, how about yours? The bolt fit is pretty snug just like it is on a nice new tight DI gun. Mine is the SOCOM barrel profile, too. Thank you for your time. My bolt was tighter than normal. The fact that mine is chrome lined & yours is not is very odd. I guess the only thing consistent with colt is inconsistency. It's more of an evolution to the platform, which is why there are different revisions out there. They are both the same one piece bcg. I understand the revision from the two piece bcg to the one the one piece bcg, but one one piece bcg chrome lined & another one piece bcg not? I'm sure there is an engineering reason behind it. |
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Did you have trouble trying to reinstall the bolt? Was it tight? Mine appears to have a socom profile barrel, how about yours? The bolt fit is pretty snug just like it is on a nice new tight DI gun. Mine is the SOCOM barrel profile, too. Is the barrel simply a MEDCON? Or does it have the M203 mounting flats? With the Army going to RO921HB barrels exclusively for new purchases, it probably makes sense to start "upgrading" the commercial lines around the "milspecs" regardless of any other reasons - conceivably, and potential replacement for the M4/M4A1 will use a similar barrel profile anyways. ~Augee |
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Did you have trouble trying to reinstall the bolt? Was it tight? Mine appears to have a socom profile barrel, how about yours? The bolt fit is pretty snug just like it is on a nice new tight DI gun. Mine is the SOCOM barrel profile, too. Is the barrel simply a MEDCON? Or does it have the M203 mounting flats? With the Army going to RO921HB barrels exclusively for new purchases, it probably makes sense to start "upgrading" the commercial lines around the "milspecs" regardless of any other reasons - conceivably, and potential replacement for the M4/M4A1 will use a similar barrel profile anyways. ~Augee It has the M203 mounting flats. |
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Well, I could not stand it anymore, went back to the shop and bought the 6940P. Have it apart on the kitchen table as of now. It does not have any internal chrome in the carrier as stated earlier. My carrier has a grainy, greenish finish on it, being the newer 1 piece design also. Overall finish is very nice with no scrapes or scuff marks.
I had a little trouble getting the piston back in the plug, due to the piston rings. I suppose they will wear in after a few hundred rounds. Hope to take it out this weekend for a run, This was the first 6940P my dealer had received, thought I might as well jump on it, or regret it later when it was gone. Neat design< I hope it shoots as good as it looks, OH, and thanks Melvin_Johnson, you got me started on this |
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I am no expert but its seems close to the Adams Arms style. With additional parts to the piston with the rings and such. I do like the carrier to the colt more due to the landing support for the op rod.
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Had a brainfart this morning, does anyone know if the bolt gas rings are the same rings for the piston?
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Had a brainfart this morning, does anyone know if the bolt gas rings are the same rings for the piston? Yea same bolt & rings as a DI. Only the carrier is different. |
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Did you have trouble trying to reinstall the bolt? Was it tight? Mine appears to have a socom profile barrel, how about yours? The bolt fit is pretty snug just like it is on a nice new tight DI gun. Mine is the SOCOM barrel profile, too. Is the barrel simply a MEDCON? Or does it have the M203 mounting flats? With the Army going to RO921HB barrels exclusively for new purchases, it probably makes sense to start "upgrading" the commercial lines around the "milspecs" regardless of any other reasons - conceivably, and potential replacement for the M4/M4A1 will use a similar barrel profile anyways. ~Augee Mine has the flats too. |
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Are you asking if the sets of gas rings on the piston and bolt are interchangeable?
The gas rings on the piston are smaller in diameter than the ones on the bolt. Quoted:
Had a brainfart this morning, does anyone know if the bolt gas rings are the same rings for the piston? Posted Via AR15.Com Mobile |
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Thanks, was thinking of replacement parts in my sleep the other night, had a hard time getting the piston back into the cup. Maybe easier after shooting a few hundred rounds. I really like the looks of this rifle, thanks for your reply.
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