Modern Sporter - Build Discussions
- Thread starter ATRS Shaun
- Start date
Thanks for the replies. Guess there are a few options available.
I think the buffer tube would have to back out 2 turns to be enough, so the buffer stop won't be held in place. I suppose this doesn't matter too much with the way the MS comes apart. I guess I'll either do that or trim a spare buffer until I can look into the PWS tube.
I think the buffer tube would have to back out 2 turns to be enough, so the buffer stop won't be held in place. I suppose this doesn't matter too much with the way the MS comes apart. I guess I'll either do that or trim a spare buffer until I can look into the PWS tube.
I was extra careful aligning the block this time around (not making that mistake again) and after a few hundred rounds noticed zero blowby on the stainless barrel, so I'm fairly confident its aligned adequately.
I opted to use the retainer pin with the JP system for the sake of keeping it from flopping out in the mud if I disassemble in the field, I'll try without it and back the tube out 360.
Thanks for the reply!
Happened to my build as well. Bcg wasn’t traveling back far enough. Initial thought it was gas tube out of alignment. Upon inspection that wasn’t the issue. Ordered a new Stag tube, spring and buffer from Arms East. Worked perfectly after. The buffer tube I had laying around and used the first time was out of spec from what I can tell. Upon installing the Stag parts runs 100%. The bcg then has the clearance against the back of the bolt catch it needed.
hannibal.black98
CGN frequent flyer
x2!!!
Merovingian
CGN Regular
- Location
- West Coast
Looking for some help for a AR type platform newbie. 
I got my Modern Sporter assembled last night and took it up to the range today for its first 50 shots. I had 3 different ammo types,
AE 5.56 green tips 62gr,
Winchester 223 white box 55gr
and a few hornady match 223 73gr ELD Match.
About 20 times within those first 50 shots the BCG would not pick up another round. There were no jams, just lots of clicks with an empty chamber when i was expecting a boom. The Winchester fared the worst, i don't think i got more than 2 consecutive shots off before it would fail to strip a fresh round. Bolt is fully forward in the chamber, just didn't pick up the next round. The AE 5.56 did the best and fed about 25 rounds and only failing to chamber maybe twice.
I noticed something that stuck me as strange and i'm sure it screams out the problem to you more experienced guys. I noticed after the last round fired on any given mag the BCG would be locked back but would be forward about and inch there by blocking the first round of the next mag, requiring me to pull the charging handle back which then caused it to seat in its proper locked back position. Im guessing i have a problem in one of these 3 areas. The gas block, bolt gas rings & buffertube spring. My thought is perhaps the bolt is not getting enough gas to send it reliably to the rear of the receiver while cycling, or perhaps the buffer spring is too heavy? Here are some of my build parts and a pic of the problem.
-JP Silent capture buffer system using the black spring ( came with 4 different weight springs i think)
-JP Full mass BCG with Enhanced JP bolt 223
-Maple Ridge Armoury 18.6″ Match V1 Nitride SPR Straight fluted 223 Wylde Barrel
-SLR Adjustable Gas block
-Geissele ssa-e Trigger
- Radian raptor CH, BCM LPK
I got my Modern Sporter assembled last night and took it up to the range today for its first 50 shots. I had 3 different ammo types,
AE 5.56 green tips 62gr,
Winchester 223 white box 55gr
and a few hornady match 223 73gr ELD Match.
About 20 times within those first 50 shots the BCG would not pick up another round. There were no jams, just lots of clicks with an empty chamber when i was expecting a boom. The Winchester fared the worst, i don't think i got more than 2 consecutive shots off before it would fail to strip a fresh round. Bolt is fully forward in the chamber, just didn't pick up the next round. The AE 5.56 did the best and fed about 25 rounds and only failing to chamber maybe twice.
I noticed something that stuck me as strange and i'm sure it screams out the problem to you more experienced guys. I noticed after the last round fired on any given mag the BCG would be locked back but would be forward about and inch there by blocking the first round of the next mag, requiring me to pull the charging handle back which then caused it to seat in its proper locked back position. Im guessing i have a problem in one of these 3 areas. The gas block, bolt gas rings & buffertube spring. My thought is perhaps the bolt is not getting enough gas to send it reliably to the rear of the receiver while cycling, or perhaps the buffer spring is too heavy? Here are some of my build parts and a pic of the problem.
-JP Silent capture buffer system using the black spring ( came with 4 different weight springs i think)
-JP Full mass BCG with Enhanced JP bolt 223
-Maple Ridge Armoury 18.6″ Match V1 Nitride SPR Straight fluted 223 Wylde Barrel
-SLR Adjustable Gas block
-Geissele ssa-e Trigger
- Radian raptor CH, BCM LPK
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juancarlos
CGN frequent flyer
- Location
- The Island
Bolt not traveling far enough back perhaps. I think this was recently mentioned in this thread with some potential fixes.
PinaKaleada
CGN Regular
- Location
- South of most
It seems like the bolt catch is catching on the carrier, and not the bolt.
Question to you, are you able to pull the BCG all the way back, and have the bolt catch catch onto infront of the bolt?
Question to you, are you able to pull the BCG all the way back, and have the bolt catch catch onto infront of the bolt?
Last edited:
Looking for some help for a AR type platform newbie.
I got my Modern Sporter assembled last night and took it up to the range today for its first 50 shots. I had 3 different ammo types,
AE 5.56 green tips 62gr,
Winchester 223 white box 55gr
and a few hornady match 223 73gr ELD Match.
About 20 times within those first 50 shots the BCG would not pick up another round. There were no jams, just lots of clicks with an empty chamber when i was expecting a boom. The Winchester fared the worst, i don't think i got more than 2 consecutive shots off before it would fail to strip a fresh round. Bolt is fully forward in the chamber, just didn't pick up the next round. The AE 5.56 did the best and fed about 25 rounds and only failing to chamber maybe twice.
I noticed something that stuck me as strange and i'm sure it screams out the problem to you more experienced guys. I noticed after the last round fired on any given mag the BCG would be locked back but would be forward about and inch there by blocking the first round of the next mag, requiring me to pull the charging handle back which then caused it to seat in its proper locked back position. Im guessing i have a problem in one of these 3 areas. The gas block, bolt gas rings & buffertube spring. My thought is perhaps the bolt is not getting enough gas to send it reliably to the rear of the receiver while cycling, or perhaps the buffer spring is too heavy? Here are some of my build parts and a pic of the problem.
-JP Silent capture buffer system using the black spring ( came with 4 different weight springs i think)
-JP Full mass BCG with Enhanced JP bolt 223
-Maple Ridge Armoury 18.6″ Match V1 Nitride SPR Straight fluted 223 Wylde Barrel
-SLR Adjustable Gas block
-Geissele ssa-e Trigger
- Radian raptor CH, BCM LPK
Seems like an under gassing issue
Mumbles Marble Mouth
CGN Ultra frequent flyer
- Location
- Lower Mainland
Try taking out that silent buffer and put in a standard buffer. Your bolt isn’t coming back far enough to pick up the next round. I fixed a stag 10 with the same issue and had the silent buffer. Changed his gas block to adjustable to get it to work with the silent buffer.
