Take down pin problem

[JJ109]

17 minutes ago, survivalshop said:

Bottom one is the 308AR Bolt Catch, the top is a std AR 15 . 

  Since you have a 80% Lower , the machining may not be to spec's , the depth of the Channel for it may not be deep enough . 

 Can you manually hold the Bolt Catch in & have it hold ?

Yea it holds without manually holding the catch in with empty mag. Not to happy with the BCG on my upper. 

[98Z5V]

2 hours ago, JJ109 said:

Yea it holds without manually holding the catch in with empty mag.

That's what it's supposed to do.  If you pull the charging handle back on an empty mag, the assembled bolt carrier should lock to the rear. Locking open on an empty mag is the design of the system. 

If the rifle passes that test, there shouldn't be any reason that you can't manually lock the bolt to the rear, as well, with no magazine in the rifle.

 

Edited September 5, 2016 by 98Z5V

[shepp]

26 minutes ago, 98Z5V said:

That's what it's supposed to do.  If you pull the charging handle back on an empty mag, the assembled bolt carrier should lock to the rear. Locking open on an empty mag is the design of the system. 

If the rifle passes that test, there shouldn't be any reason that you can't manually lock the bolt to the rear, as well, with no magazine in the rifle.

 

And with out the mag you have to manually operate the catch. I went back and read everything, which kinda jumps around a lot so I wanted to clear that up

[98Z5V]

Take that accu-wedge out, also.  Lock the pins on the upper and lower, and try it without the accu-wedge.  Report results.

 

Oh, that's not a DPMS G2 rifle.  Despite the measurement on the upper, it's a first generation series, before the G2.

[survivalshop]

6 hours ago, JJ109 said:

Yea if i hold the upper down to the lower it will hold. 

Something is not correct if you have to do this , but you say it will catch & lock back the BCG on an Empty Mag . 

[JJ109]

3 hours ago, survivalshop said:

Something is not correct if you have to do this , but you say it will catch & lock back the BCG on an Empty Mag . 

Yea i dunno. It works like i said. The play seems extreme between the receivers. 

7 hours ago, 98Z5V said:

Take that accu-wedge out, also.  Lock the pins on the upper and lower, and try it without the accu-wedge.  Report results.

 

Oh, that's not a DPMS G2 rifle.  Despite the measurement on the upper, it's a first generation series, before the G2.

 

The only way i can get the bolt to lock back is with the accu wedge out and me holding the receivers tight together. Double check on my bolt catch and is definitely a 308 catch. I open up my ar15 to compare. 

[98Z5V]

Locks back with an empty magazine it...  You stated that.  Or, are you forcing something else, AND locking it back with an empty magazine... 

 

We need all the details at once, not piecemeal...

[JJ109]

9 hours ago, 98Z5V said:

Locks back with an empty magazine it...  You stated that.  Or, are you forcing something else, AND locking it back with an empty magazine... 

 

We need all the details at once, not piecemeal...

Thats it. Play between receivers and that gap is closed the bolt will lock back. I think if i can find or make a JP tension pin it will work. 

[survivalshop]

 Have you test fired this rife yet ?

  With the rifle shot gunned or with the Upper Receiver off , insert & seat an empty mag. in the mag well & take the best measurement on how high the Bolt Catch is raising above the Lower Receivers shelf , the flat area in front of the Hammer . I had photo's of how to measure , but they are gone , but its a simple height measurement . I used a Digital Caliper or dial caliper will work . 

 If the Pins are snug or good fit in the Lower Receiver , its the Upper Receivers Pin holes that are a loose fit , I think you can just alter the Bolt Catch stop area , to let the Catch raise a little more to engage the Bolt . WE need a measurement of how high the Catch is raised by the Mag to compare with ours .

 

[JJ109]

2 minutes ago, survivalshop said:

 Have you test fired this rife yet ?

  With the rifle shot gunned or with the Upper Receiver off , insert & seat an empty mag. in the mag well & take the best measurement on how high the Bolt Catch is raising above the Lower Receivers shelf , the flat area in front of the Hammer . I had photo's of how to measure , but they are gone , but its a simple height measurement . I used a Digital Caliper or dial caliper will work . 

 If the Pins are snug or good fit in the Lower Receiver , its the Upper Receivers Pin holes that are a loose fit , I think you can just alter the Bolt Catch stop area , to let the Catch raise a little more to engage the Bolt . WE need a measurement of how high the Catch is raised by the Mag to compare with ours .

 

Will do......... It has not been fired yet. It supposed to be head spaced correctly from sota arms. I would like to buy the tools and check it myself. 

[JJ109]

1 hour ago, survivalshop said:

 Have you test fired this rife yet ?

  With the rifle shot gunned or with the Upper Receiver off , insert & seat an empty mag. in the mag well & take the best measurement on how high the Bolt Catch is raising above the Lower Receivers shelf , the flat area in front of the Hammer . I had photo's of how to measure , but they are gone , but its a simple height measurement . I used a Digital Caliper or dial caliper will work . 

 If the Pins are snug or good fit in the Lower Receiver , its the Upper Receivers Pin holes that are a loose fit , I think you can just alter the Bolt Catch stop area , to let the Catch raise a little more to engage the Bolt . WE need a measurement of how high the Catch is raised by the Mag to compare with ours .

 

10.5 mm or about 0.42inchs above lower shelf when mag is locked into mag well. 

[survivalshop]

Ok , this readings are off my DPMS Lower , both of mine are DPMS LR's so I only did the one closest in the safe

CProducts ( org. )    0.455"

Lancer L7                0.540"

DPMS                      0.540"

PMag ( org. )            0.495"

PMag Gen 3             0. 473"

 What Mag brand are you using ?   It might be a Brand issue , I had a early CMMG Billet Lower Build that worked with any Steel mag, but not the org. PMag . When the Gen 3 PMag came out it worked fine in the rifle , as did the Lancer .  

[survivalshop]

double post , wtf 

Edited September 6, 2016 by survivalshop

[98Z5V]

There's a way to knock the bottom corner off the bolt catch to allow more upward travel.  I had to do that on my first Aero lower build.  I'll try to find the pics.

[JJ109]

6 hours ago, survivalshop said:

Ok , this readings are off my DPMS Lower , both of mine are DPMS LR's so I only did the one closest in the safe

CProducts ( org. )    0.455"

Lancer L7                0.540"

DPMS                      0.540"

PMag ( org. )            0.495"

PMag Gen 3             0. 473"

 What Mag brand are you using ?   It might be a Brand issue , I had a early CMMG Billet Lower Build that worked with any Steel mag, but not the org. PMag . When the Gen 3 PMag came out it worked fine in the rifle , as did the Lancer .  

Pmags. ..... Buddy had a WMD nixb BCG laying around. Grab it from him and stuck it in. Without the accu wedge in it catching sometimes. Like every 2 out of 3 times. Might be worth trying a different mag????

[survivalshop]

  With out the Mag inserted & manually holding the Bolt Catch in , does it hold the BCG locked back ?

 As 98 is referring to & I have in other posts here, if the Bolt Catch can be altered to be raised higher if the Bolt catch is stopping or at the end of its travel . Thats if the its stopping & pushing down on the Mag follower , keeping the Follower from pushing the Bolt Catch to its full upward movement or travel .

  This photo is a little blurry , & its a 308AR Bolt Catch, Beside an AR 15 , but it shows the difference in how the angle of the travel stop portion of the 308 AR , this is where you can take material off to increase the travel of the Bolt Catch , keeping the angle , just taking off a little at a time , a Stone or good file will do , it won't take much . This is only needed if the Mag's Follower is not being able to force the Bolt Catch with in its full Travel .

  Your 80% Lower may not have had the channel in the Lower Receiver milled properly or because of the fit of the Receivers , it may not be enough . Also you may want to inspect the Spring Hole & the Channel , to make sure there are no debris in there keeping it from full travel . Not to mention the correct Spring in there.

 

Edited September 7, 2016 by survivalshop

[JJ109]

On 9/6/2016 at 9:00 PM, survivalshop said:

  With out the Mag inserted & manually holding the Bolt Catch in , does it hold the BCG locked back ?

 As 98 is referring to & I have in other posts here, if the Bolt Catch can be altered to be raised higher if the Bolt catch is stopping or at the end of its travel . Thats if the its stopping & pushing down on the Mag follower , keeping the Follower from pushing the Bolt Catch to its full upward movement or travel .

  This photo is a little blurry , & its a 308AR Bolt Catch, Beside an AR 15 , but it shows the difference in how the angle of the travel stop portion of the 308 AR , this is where you can take material off to increase the travel of the Bolt Catch , keeping the angle , just taking off a little at a time , a Stone or good file will do , it won't take much . This is only needed if the Mag's Follower is not being able to force the Bolt Catch with in its full Travel .

  Your 80% Lower may not have had the channel in the Lower Receiver milled properly or because of the fit of the Receivers , it may not be enough . Also you may want to inspect the Spring Hole & the Channel , to make sure there are no debris in there keeping it from full travel . Not to mention the correct Spring in there.

 

Well have an update. Went down to local gun shop that i deal with and brought my bolt catch with me. They had a Seekings Precision AR-15 enhanced bolt catch that measured slightly higher and had more throw when empty mag in place. It was $11.00.  .. It works perfectly with more then enough catching the bolt every single time. Its much stronger from what Seekings website says. 

[survivalshop]

 That's Great , now go out & have fun & give us a range report .

[JJ109]

7 minutes ago, survivalshop said:

 That's Great , now go out & have fun & give us a range report .

Well waiting on the optics now LOL. Going to break her in with some iron sights to scope comes in. Survival thanks for thr help.