Long time reader, first time poster! I figured I'd post up a video I made yesterday to share one of my new toys. It's a 6" .300blk upper.
Originally the barrel started off as a 9.5" Core15 barrel. However with my 9" Arbiter Ti can the overall length was 18", which was pretty long, I didn't care for it and I wanted something more compact. I decided to take off a few inches and brought it down to 6", which is as short as you can really go. I have considered going down to 4.5" and welding up the gas port, and making a new one, but I decided for simplicity I'll keep the pistol length port and try and get it to work, I can always go shorter if I want to.
As you can see the gas block is against the flash hider, literally no more can be taken off. This leaves me with a very short dwell time.
Once you add the can on it ends up at 14.5", back to a normal length.
Then I slip over the Samson EVO 11" rail and it protects my can from being damaged from drops and other debris. Not to mention keeps me from being burned.
After the first cut the gun wouldn't cycle. I measured the factory gas port around .086" which is pretty small. I opened it up to .096" and it began to cycle 2-3 rounds, but was still under gassed. My last step was .109" and now it is cycling well. The cyclic rate is around 800rpm, which is a really nice. It will still need a little more extensive testing, but it sure is fun to finally hear a .300blk clicking away that's a reasonable size.
https://www.youtube.com/watch?v=0M6ibP_k6pc
Here's a video of the upper running and a little overview about how it's set up.
I decided to share this build because there really is no info out there for this short of a barrel. I could not find any gas port data at all. So, because of that, I decided do the work and give back what I learned to help others. It is fun having a quiet gun that doesn't feel like a pike in your hands. Also, another added benefit is the gun is quite light also!
Originally the barrel started off as a 9.5" Core15 barrel. However with my 9" Arbiter Ti can the overall length was 18", which was pretty long, I didn't care for it and I wanted something more compact. I decided to take off a few inches and brought it down to 6", which is as short as you can really go. I have considered going down to 4.5" and welding up the gas port, and making a new one, but I decided for simplicity I'll keep the pistol length port and try and get it to work, I can always go shorter if I want to.
As you can see the gas block is against the flash hider, literally no more can be taken off. This leaves me with a very short dwell time.
Once you add the can on it ends up at 14.5", back to a normal length.
Then I slip over the Samson EVO 11" rail and it protects my can from being damaged from drops and other debris. Not to mention keeps me from being burned.
After the first cut the gun wouldn't cycle. I measured the factory gas port around .086" which is pretty small. I opened it up to .096" and it began to cycle 2-3 rounds, but was still under gassed. My last step was .109" and now it is cycling well. The cyclic rate is around 800rpm, which is a really nice. It will still need a little more extensive testing, but it sure is fun to finally hear a .300blk clicking away that's a reasonable size.
https://www.youtube.com/watch?v=0M6ibP_k6pc
Here's a video of the upper running and a little overview about how it's set up.
I decided to share this build because there really is no info out there for this short of a barrel. I could not find any gas port data at all. So, because of that, I decided do the work and give back what I learned to help others. It is fun having a quiet gun that doesn't feel like a pike in your hands. Also, another added benefit is the gun is quite light also!
