survivalshop

Need to see a photo of where your Gas Tube is positioned in the Upper Receiver , use a flash light if not enough light for a clear photo . Take a photo of you Bolt Face with the EMPTY Mag in the rifle holding the Bolt Catch engaged with the Bolt also. This build of yours is why we recommend using Receivers from the same manufacturers , Tolerance stacking can make even your best efforts useless . I find it strange that with that large of Gas Port in the Barrel that you are not witnessing heavy recoil when firing , even with the inside diameter of the gas tube @ 0.120" which is a reduction of your Barrels Gas Port hole , but you should be over gassed , something is not correct , of course. Are you holding the Bolt Catch in while you are slamming your rifle down ? If not , they will all drop the BCG , maybe even with a empty Mag installed , most may drop the BCG . Its not what the Bolt Catch is designed for . I have no desire to try this test. If I remember correctly , this is a 80% Lower receiver you finished , no offense to you, but it is a possability that you finished spec's may not be correct & it may be effecting you Bolt Catch engagement. The Bolt Catch travel can altered if not raising enough to engage the Bolt Face properly. The 0.900" is almost an inch , I put a zero where it didn't belong.I fixed it .

Nice , persistence pays off .

Oh , well that one is meaningless .

Has to be manufactured before May of 1986 to be a pre-ban.

I've been looking at small Mills & lathes lately , I thought about a Combo , but am thinking separate machines now . Those CNC's are kinda cool to be able to program them via PC , I just think they are too light duty for what I want.

As long as you use a AR 10 Bolt with the AR 10 Barrel Extension , it should work . There are slight dimensional differences with the Barrel Extensions/Bolts, so the common thought is to match Bolts to there Barrel Extensions . Now what you use for a Receiver Extension & the Buffer System , Keep that AR 10 or LR DPMS . The Armalite pushers here should have better info .

The Pin hole to the long end of the Bolt Stop as best as I can measure is 0.900" & the short end is 0.120" These measurements are not exact but close, had a hard time getting centered in the Pin hole.

By just visual inspection , does the Gas Tube sit in the Upper like the photo above ? The Gas Tube should be in the middle of the Cam Pin recess in the Upper as in the photo . Is the Bolt Stop easy to move with no binding , the Magazines spring is kinda weak when the Follower is at the top of the Mag. & any binding will not permit the Bolt stop to raise enough to engage the Bolt . Is the correct Spring in use for the Bolt Stop , it can be confused in the Lower Receiver parts group .

Some interesting machines for small work . BoxZy ( loaded ) $ 3899

Thats a good one !

New Build is not like a factory rifle where their R & D has come up with proper manufacturing of components for an assembly line that can assemble the Rifle & it function out of the gate . You are the R & D , assembler & Gunsmith , to make the proper fitment of said components . Some of & even some Factory rifles need a break in for proper function of the Action . Run it Wet is our motto here for break in , no matter where the rifle comes from or is built . It is some what true that most rifles like or should I say shoot better with certain ammo , saying that , most if not all , will shoot just about any 7.62x51/308 , just the Barrel/Chamber will prefer one bullet/charge more then others . It is also true that using a steady diet of high pressure ammo will degrade the service life of a Barrel . Your fast Shepp

Like this

How far does your Gas Tube protrude into the Upper Receiver ? Can you get a photo of it for us . Another thing is , you may have a fitment problem out of spec Bolt Stop . Even though you can manually engage it & it hold the BCG , it may have a Burr or may not be able to have full travel . I can pull one of mine off to get the measurement that you wanted . If you can Charge the Action & manually engage the Bolt Stop & it function as to spec's , there is nothing wrong with the Buffer system travel , doesn't rule out something else with in the system . Are there any marks on the threads for the Receiver Extension , where the BCG could be hitting ? You are close to a fully functional rifle , if its only the Bolt stop not engaging properly , but there is one thing bothering me & that is , with that big Gas Port in the Barrel , why is there not signs of over gassing ? It should be pounding the action back . May have something to do with Gas Tube length , there are two different lengths of Rifle length Gas Tubes , one is DPMS & the other is AR 10( Armalite ).

Nope & I don't have a 308 bolt stop not in a Rifle . As shown , correct buffer spring for a DPMS type 308AR , Rifle Stock ,is around 12 3/4" long & has 39 coils , anything else may cause issues . I think the one from my 20" being 12 1/2 " long is with in spec for a well used Spring , most likely it needs replacing. I would adj. the Gas Block per manufacturers instructions , as has been said above . BCG moving too fast & bouncing off the bottom of the Receiver Extension could overcome the Bolt Stop , I've seen them break .

Don't see how a round can be set off by impacting a flat surface on the Mag. , just doesn't jive . A high set primer might & the power released from it exploding could set off the round under it . Also a high primer could go off before it was completely chambered , All speculation on what happened ,of course , as was said . Double charges are very deadly . Its why I use Powders that a double charge will over flow the case or make it so a Bullet will not seat , takes away any probability of it happening. Would of liked to see photo's with the Pistol unmolested after incident , might tell more .

It would be with the Lower Receiver Parts group . How is it functioning other wise , ejecting & extracting OK ?

Does it lock back with just an empty mag. when pulling the Charging handle back all the way ? Do you have a 308AR Bolt Stop installed, they have a larger pad then the AR 15.

I'm in St Augustine , used to work in downtown Jax before I retired .

You can tell the difference in the noise of the Action , when Charging , makes a more distinctive metallic sound . I think everyone should at least shoot one, in their life time . I have had a bunch of them ( was a FFL for twenty years ), I really like the one I kept , they are beautiful . The loading of the N block is easy , you only have eight to push in there & once you get used to it , its a breeze .

I looked at my 308AR rifle stock Buffer Springs to see what coil count & Spring length they were to see how they compared to what a Member KnewB had in his rifle & I find that the New 18" build has a strange spring in it , well not so strange , its an AR 15 Rifle stock size , Buffer Spring , by length & Coil count . Now this Buffer Spring is in a New build as said , which I'm having strange issues in & if you go to 308, Parts & under D.Wilson Bolts , you will see what I'm talking about , Rifle functions flawlessly with all the other Bolts I have tried in it , but his & its not just one of his Bolts , its also a complete BCG , acting the same way , odd , for sure . So me installing a AR 15 Rifle Buffer Spring , which was ordered , not sure who yet but will find out because , I have no doubt I ordered the correct spring . The thing is , I took it for granted I got the correct spring & to be honest , I , until the other day didn't know what the spec's were for the correct 308AR rifle spring for a DPMS LR . MY Bad ! Now I know & I have uncovered , at least to me , some interesting measurements on the group of springs I have on hand . I will be installing the Tubb's Flat wire Buffer Spring I have in the 18" bbl'd rifle . I have a DPMS, 308AR Carbine Spring , the Spring that came out of the 18" Rifle & two AR 15 Rifle Stock Buffer Springs . Top to Bottom,- 308AR Rifle Buffer , DPMS (from my 18"Rifle ) - AR 15 Rifle Buffer ,- AR 15 , Rifle Stock Buffer Spring , Buffer Spring from my 18" Rifle , DPMS ,308AR Carbine Buffer Spring ( correct ) Measurements. DPMS Rifle Buffer - 5 1/4 " long AR 15 Rifle Buffer - 6 " AR 15 Rifle length Buffer Spring (# 1 ) - 12 3/8 " long , 43 Coils + ( # 2 ) 13 1/8 " long , 44 Coils . Spring from my 18" Rifle - 12 1/4" long , 43 Coils . We have plenty of Carbine info around here , so I will keep this just Rifle length stuff , but I will say that all the Springs had a Wire Diameter of 0.071" , Now, I know they can make Springs with different Tensions , but this measurement surprised me . CS ( Tubb's ) Flate Wire Buffer Spring ( Rifle or Carbine ) 18 5/8 " long , I didn't bother to count the Coils or their thickness , this Spring is a Bear to get in a Carbine , but not all that bad in a Rifle length Receiver Extension. We have seen others who had AR 15 Rifle Buffer Springs here before , I did' think I would be one , you can't take anything for granted with these builds . You are at the mercy or the Parts you are shipped I thought I was doing a good job weeding the incorrect ones out & this time I got bit for not knowing & checking the components out . Just so you know my old 20" 308AR with DPMS Lower , has the correct Rifle Buffer Spring , 12 1/2 " long , 39 Coils .

The first time you reach under your large long range scope to charge the rifle , you will wish you had a Tacops !

A good sealing Gas Block may be all that is needed to straighten your rifle out . The large Gas Port in the bbl. may still be an issue , but with the adjustability & stronger material , may be just what you need .

Barrels like different ammo , why not Propellant . Nice , Barrel seems to like the 175 gr.Bullet /40 gr. powder.

I have a Tubb's , Flat Wire Spring to put in there . Your Buffer should come close to the end of the Receiver Extension . Its a fine line the way this ASR's are engineered , Springs & Buffers & the Receiver Extension have to be all of the same System , be it a DPMS LR 308 type or the AR 10 . Its a balance of spring pressure /length & Buffer weight to Cycle correctly . The Buffer may contact the end of the Receiver Extension when fired , but if it does , its should be light tap & may be more with higher powered loads . The fact that you can lock the Bolt back shows its not set up too short & the BCG has the ability to cycle that far fiscally, when fired & it will not Lock Back , its could be a couple of things , Short stroking can be too weak of Gas Signal , rough Chamber to incorrect components or even tolerance stacking. the one in the 18" The one in the 20"

I was looking up what the spring length & Coil count of DPMS 308AR's for knewB in the Introduction Thread & pulled both my DPMS Rifle Buffers & Springs & found that my old 20" had the correct Spring , but it looks like I was sent a AR 15 Rifle length spring or this one in the 18" was cut wrong, see below , 20" bbl 3098AR - 39 Coils , 12 1/2 " long ( 39 Coils & 12 3/4" is normal ) 18" bbl. 308AR - 43 Coils , 12 1/4 " long . ? This may be why this Bolt doesn't work or contribute to it . Maybe , I will take Wire diameter of the two & I have a New AR 15 Rifle Spring in the Parts drawer.& I will install the Tubb's Flat Wire Spring I have & find out Monday.