DSA now making M 4 type rifles

[nathan]

They are known for FN Fals but are now into M 4s.
http://www.aimsurplus.com/product.a...e=DSA+Z4+MidLength+5.56/.223+Rifle&groupid=11

http://www.dsarms.com/DSA-ZM4-Mid-Length-Carbine----DSZM4MIDLENGTH/productinfo/DSZM4MIDLENGTH/

 

[12131]

DSA now making M 4 type rifles

Kind of old news.

 

[Robert]

They have been doing that for years now. Decent quality from what I understand.

 

[wally]

I'm happy with my DSA midlength, I've the fluted barrel model -- just wanted something a little different, function has been 100% and so far its shot nothing but cheap steel cased ammo.

 

[nathan]

Spikes midlength vs DSA midlength, which would be your pick ? Both have 5.56 chamber but Spikes has the 1 is to 7 twist vs 1 is to 9 with DSA.

 

[TonyAngel]

I'd go with the Spike's and for reasons other than just the twist. The Spike's is built using milspec parts which, if nothing else, gives me a bit of peace of mind.

 

[ny32182]

I bought one of the DSA 16" carbine uppers with nitrided barrel for $280 when they first came out.

Let me stress I have NOT put very many rounds at all through it, but so far it has exhibited relatively weak ejection in terms of just dribbling cases out the side. I suspect this means it is under or overgassed, but not really sure which. It has not malfunctioned, but my impression of it is that it is not up to the standards to which they build their FALs, which I have two of. That said, it was $280, so I wasn't expecting milspec quality. The M4 ramps are lined up, the sights didn't need to be cranked way in any direction to zero, the finish is uniform, the FH is timed with the top port straight up (can't say that about all my milspec-grade rifles), etc. I also use it to run my CMMG .22 conversion, and if I ever get the urge to practice paint jobs, etc, this upper will make a fine candidate.

 

[TonyAngel]

ny, change the rings. One thing about the lesser expensive options in ARs is that those kits sometimes come with sub standard small parts, although the major parts are serviceable.

Also check your gas key and make sure that it's on tight and that you don't see a pattern of carbon around it indicating a gas leak. It could be other things, but these two are the easiest to check.

 

[ny32182]

The BCG is a BCM and everything appears good on it to me.

 

[TonyAngel]

No, BCM has a good BCG. I'll tell you, I had at one time purchased a "cheap" barrel from a vendor just because I heard good things about them. I also purchased a gas tube to go along with it. The short of it is that the tube turned out to be defective. It was out of spec and not getting a good seal in the key. They sent me another one and I had the same problem. I just ordered another from BCM and my problems went away. Check around your gas block. Around the barrel and around where the tube goes into the block and see if you notice evidence of excessive leakage. Swapping the tube may be something that could help. It's also possible that the gas port in your barrel is a little too small or that you are running a buffer that is too heavy. It's also possible that the gas block port isn't centered over the barrel port.

OK, just consider the above as food for thought. No way that I can diagnose this without having my hands on the rifle. Personally, I'd tear the whole upper apart and reassemble it.

 

[ny32182]

Next time out I was planning to switch from an H to standard weight carbine buffer to see of that helps, and I'll watch for leakage anywhere in the vicinity of the FSB.

I've also heard that an over gassed rifle can try to extract early and cause poor extraction because it is trying to yank a case that is still partially sealed in the chamber. Seems to me that if the pressure was still high enough to partially seal the case, that any unlocking would lead to a KB, but who knows; that is the nice thing about information on the internet.

 

[TonyAngel]

I don't think that what you are describing is the result of over gassing. An over gassed rifle will usually FLING the brass forward at around the 1 to 2:00 position. Cases getting stuck due to over gassing is usually an issue with steel cased ammo. I really don't think that I've seen an over gassing situation that didn't either fling the brass or tear the rims off of the cases. I've never seen over gassing cause "weak" ejection.