07-20-2013, 02:42 AM
Well it looks like I may have figured it out. I really won't find out for sure until tomorrow.
I haven't really dedicated that much time to working on this issue as I was hoping that it was an ammo issue and I finally finished off whatever left over ammo I had made up today.
I went to the range today to work up a new load using IMR 8208. Hoping that a different load would yield different results. I really didn't think it would change anything but hey what the heck anything is worth a shot right...
So anyway. I got to the range today and about 5 miles from the range it starts to pour down rain on a 10% chance of Precipitation day....so after pulling 3 people out of the mud and cleaning up a bit. The range owner gave me free reign of the range (Everyone else left, including the owner/range officer)
I had cleaned the gun and removed my scope Quick Detatch BoBro mount so I decided to use some of my left over ammo for a control and to make sure it was still somewhat zero'd. I fire 3 rounds at 100 have a nice little group about an 1" and then proceed to shoot a steel 4" hanger at 200. I record a hit and proceed out to 400. I fire 3 rounds at a metal target and make good hits. And move up to 500 and fire 5 shots at the metal plate and afterwards I get off my table and go walk out and take a look. All is well everything is shooting as expected.
So I do my testing on my reloads 27.7, 27.9, 28.1, 28.3, and 28.5 of IMR 8208
I fire 3 rounds of 27.7 zoom in to see how it went. Hmmm.... all misses. So I dial back down my scope from 3.5 mils back to zero where it belongs and move on to 27.9, 28.1 and so on firing 3 rounds each per load.
BTW: 27.9 and 28.1 were the best and very similar. I did take my chrony but decided not to use it.
After getting a base for what a 3 shot group looked like for each round. I pull out my suppressor. (I finally get to what this topic is about)... so I fire all remaining rounds on the same targets as the loads were. And as it moved up in power loads so did the spread of my groups (If you can call it that as it looked more like a shotgun blast). 27.9 was about 5" low 28.1 was about 7" low, 28.3 was about 14" low..... I'm like WT Heck!
Dumbfounded with my results I load up some old load that I had from what I did with barnes 120 TSX I fire two rounds at 100 which are side by side and fire a 3rd round at 200 and hit the steel hanger just for kicks before I put the suppressor back on. I fire two rounds with the suppressor and its about 2" low seems acceptable to me.
So after I leave the range. (I swear the story is coming to an end soon....I think) I decide to go back to the shop I had the install of my gas block done. I speak with the gunsmith and his apprentice. After going over the gun and the suppressor they can't find anything wrong, bring out the bore scope and yada yada yada do this and that. At a certain point I thought he was going to try and blow me off and BS me. But I think he stayed with it and we talked it out. What I thought what changed and whatnot.
Anyway, to bring this to an end. It appears that it really may be the gas block that is the issue. Not really a failure of the gas block but more of an issue of a node change due to the previous gas block being pinned.
So I have a hole where my gas block was prior to me changing it. And it is believed that it is causing a harmonic imbalance when adding the suppressor causing my rounds to deflect low and be sporadic in the shot location.
It actually makes sense to me. So I'm going to cut down my old A2 gas block and put it back on the gun tomorrow. To clean it up i'm going to put a YHM free float hand guard over it. Then I'm going to take it to the range with some new loads I made when I got home of 123 SST ,IMR 8208, 28.0 @ 2.23 COAL and hope for the best.
I haven't really dedicated that much time to working on this issue as I was hoping that it was an ammo issue and I finally finished off whatever left over ammo I had made up today.
I went to the range today to work up a new load using IMR 8208. Hoping that a different load would yield different results. I really didn't think it would change anything but hey what the heck anything is worth a shot right...
So anyway. I got to the range today and about 5 miles from the range it starts to pour down rain on a 10% chance of Precipitation day....so after pulling 3 people out of the mud and cleaning up a bit. The range owner gave me free reign of the range (Everyone else left, including the owner/range officer)
I had cleaned the gun and removed my scope Quick Detatch BoBro mount so I decided to use some of my left over ammo for a control and to make sure it was still somewhat zero'd. I fire 3 rounds at 100 have a nice little group about an 1" and then proceed to shoot a steel 4" hanger at 200. I record a hit and proceed out to 400. I fire 3 rounds at a metal target and make good hits. And move up to 500 and fire 5 shots at the metal plate and afterwards I get off my table and go walk out and take a look. All is well everything is shooting as expected.
So I do my testing on my reloads 27.7, 27.9, 28.1, 28.3, and 28.5 of IMR 8208
I fire 3 rounds of 27.7 zoom in to see how it went. Hmmm.... all misses. So I dial back down my scope from 3.5 mils back to zero where it belongs and move on to 27.9, 28.1 and so on firing 3 rounds each per load.
BTW: 27.9 and 28.1 were the best and very similar. I did take my chrony but decided not to use it.
After getting a base for what a 3 shot group looked like for each round. I pull out my suppressor. (I finally get to what this topic is about)... so I fire all remaining rounds on the same targets as the loads were. And as it moved up in power loads so did the spread of my groups (If you can call it that as it looked more like a shotgun blast). 27.9 was about 5" low 28.1 was about 7" low, 28.3 was about 14" low..... I'm like WT Heck!
Dumbfounded with my results I load up some old load that I had from what I did with barnes 120 TSX I fire two rounds at 100 which are side by side and fire a 3rd round at 200 and hit the steel hanger just for kicks before I put the suppressor back on. I fire two rounds with the suppressor and its about 2" low seems acceptable to me.
So after I leave the range. (I swear the story is coming to an end soon....I think) I decide to go back to the shop I had the install of my gas block done. I speak with the gunsmith and his apprentice. After going over the gun and the suppressor they can't find anything wrong, bring out the bore scope and yada yada yada do this and that. At a certain point I thought he was going to try and blow me off and BS me. But I think he stayed with it and we talked it out. What I thought what changed and whatnot.
Anyway, to bring this to an end. It appears that it really may be the gas block that is the issue. Not really a failure of the gas block but more of an issue of a node change due to the previous gas block being pinned.
So I have a hole where my gas block was prior to me changing it. And it is believed that it is causing a harmonic imbalance when adding the suppressor causing my rounds to deflect low and be sporadic in the shot location.
It actually makes sense to me. So I'm going to cut down my old A2 gas block and put it back on the gun tomorrow. To clean it up i'm going to put a YHM free float hand guard over it. Then I'm going to take it to the range with some new loads I made when I got home of 123 SST ,IMR 8208, 28.0 @ 2.23 COAL and hope for the best.