Ultralight Ultralight Rifles

[Taudisio]

This is what it looks like... I haven't shot it yet. Trying to give the JBweld plenty of time to cure. Basically, I used a bit of the steel putty to plug the little hole, then once that was set I used the 5k psi stuff to put a piece of aluminum pipe over it. Then I used the quick set putty again to put another larger aluminum tube over the top of that one, so it would hold everything in place while it cured. The two pieces of tube weighed about 0.3oz, and I hope I didn't use more than an ounce of jbweld... so hopefully less weight than a ti gas block. Hopefully it holds...

I’m going a different route, tapping/threading it and securing it to the barrel like a standard block. My gunsmith has faith it will be fine. A side note, I have shown him the thread and he is excited about the project and was asking if there is a “need for other weirdos” for him to develop his own gas port blocker. I tried to convince him to make ultralight non-gas port barrels. I don’t know what his price point will be, but he was pondering it and said he could do it. I think he wants to make his own as a demo gun. I am heavily debating on starting a second in a 6x45, or 300blk

 

[Taudisio]

I drilled (stoped before going through to leave a solid stopping point) then tapped 4-40 into the port. Then put a stainless set screw in there that was sanded to be perfectly flush with the barrel OD. Then I had a 0.0015" undersized stainless sleeve made, and thermal fit it by heating the sleeve with an induction heater until it would drop on, about 500*f. The sleeve is .750od by 1 inch long and weighs the same as a cut down aluminum gas block. It may have been easier to just use the gas block I already have modified, but I thought this would be fun and clean looking while also hopefully last forever without issue. Last thing, I told faxon they should just made straight/no port barrels for this application and they said they'll think about it.

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Well done sir! A route I hadn’t thought about going. Have you ran some rounds through it yet?

 

[JBradley500]

Well done sir! A route I hadn’t thought about going. Have you ran some rounds through it yet?

Not yet. Everything is done except the red dot isn't here. I have a spare scope/mount I was going to test fire with, but my sling setup won't clear it. That sounds weird, but I'll post pics when it's all together to show the path I took overall.

 

[Silent_Matt]

I just used a .625 ID sleeve and some Loctite 635. Only have about 30 rounds through it, but it's held so far.

 

[Silent_Matt]

On another note, I'm thinking of cutting down my handguard...

Either I leave the the front and cut at the red line or cut the front off at the yellow line and make it like a traditional fore end.

 

[SLG]

This is a very interesting thread, thanks to all who posted about their ultralight AR parts and builds. I am going to put together an ultralight bolt action AR, based on this thread. I am wondering if anyone knows the LOP of an A2 buffertube with a Farrowtech butt like the one Thegman posted initially?

For comfort in shooting a 300HAM'R, I have to think that a rubber buttpad and CAR type stock might be best, but it probably doubles the weight compared to the bare bones options. Any thoughts on which stock offers the best balance of weight and comfort?

Also, I talked to Wilson Combat (I have a minor relationship with them) and asked Bill to make an ultralight 300 HAM'R with no gas port. Maybe 18" would be nice also. He said he would consider it.

 

[Thegman]

This is a very interesting thread, thanks to all who posted about their ultralight AR parts and builds. I am going to put together an ultralight bolt action AR, based on this thread. I am wondering if anyone knows the LOP of an A2 buffertube with a Farrowtech butt like the one Thegman posted initially?

For comfort in shooting a 300HAM'R, I have to think that a rubber buttpad and CAR type stock might be best, but it probably doubles the weight compared to the bare bones options. Any thoughts on which stock offers the best balance of weight and comfort?

Also, I talked to Wilson Combat (I have a minor relationship with them) and asked Bill to make an ultralight 300 HAM'R with no gas port. Maybe 18" would be nice also. He said he would consider it.

I've been out living in the woods for 5 weeks, but you guys have been busy!

Good to hear Bill is thinking about making portless barrels.

He made a few to try out on his own straight pull build and sent me this one. It's a 16" 20oz 300 HAM'R. I need to get it on a build, but haven't had time yet. This is ultimately the way to go if barrels like this become available. I asked Faxon about a portless barrel as well, but haven't heard back on that.

To add: A fluted PSA buffer tube and a B5 Systems CAR stock with a foam recoil pad added, adds less than 3oz over the Farrow setup. I've been moving in that direction as I find it easier to carry and more comfortable and stable to shoot. Also nice as only a single stock with the pad added is needed. It can be moved from build to build in 10 seconds. The stock I'm using is the one on the second build I posted. Cheap, simple, relatively lightweight and works well (for me).

 

[Thegman]

On another note, I'm thinking of cutting down my handguard...

Either I leave the the front and cut at the red line or cut the front off at the yellow line and make it like a traditional fore end.
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Take a look at the picture of the Red Ryder with the black bear in the first post. I cut one down like you're thinking and it works fine, though it was eventually replaced with a Jag Composites.

 

[Thegman]

I just want to thank you guys for the inspiration. I have everything ordered, by my research and calculations, I should be right at 46.605 oz! I’ll update when everything arrives!!!

46.6 oz...that's impressive. Making the Red Ryder look portly.

 

[Thegman]

Another question: what normal parts are you not using when you do a Solo 300? The bolt catch? The buffer retaining stuff? Anything else you skip or don't skip?

Those are the parts to skip. I've generally been installing the bolt catch, but plan on removing any that are still there when I have time. There's no real use for them at all with these builds.

 

[SLG]

I've been out living in the woods for 5 weeks, but you guys have been busy!

Good to hear Bill is thinking about making portless barrels.

He made a few to try out on his own straight pull build and sent me this one. It's a 16" 20oz 300 HAM'R. I need to get it on a build, but haven't had time yet. This is ultimately the way to go if barrels like this become available. I asked Faxon about a portless barrel as well, but haven't heard back on that.

To add: A fluted PSA buffer tube and a B5 Systems CAR stock with a foam recoil pad added, adds less than 3oz over the Farrow setup. I've been moving in that direction as I find it easier to carry and more comfortable and stable to shoot. Also nice as only a single stock with the pad added is needed. It can be moved from build to build in 10 seconds. The stock I'm using is the one on the second build I posted. Cheap, simple, relatively lightweight and works well (for me).

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That is a great barrel! I'd be happy with a SS version.

Any idea on LOP with your A2/Farrowtech?

 

[Thegman]

That is a great barrel! I'd be happy with a SS version.

Any idea on LOP with your A2/Farrowtech?

The Farrowtech LOP is about 13 1/2", same as a CAR stock, but it slants downward, so a little shorter at the bottom.

 

[SLG]

A little long for me, unfortunately, but thanks very much!

 

[Thegman]

Between the Tennessee Arms carbon lower and the NFA LW4, which one would come out lighter weight in the end? Say, put a KAK LPK in the TN Arms lower and the lightweight polymer LPK in the LW4, which is lighter? more durable?

My old NFA polymer lower was 3.8 oz. The TN Arms Carbon lower is 4.0 oz.

The new NFA lowers are made out of a different polymer, last I checked (Nylon 6, same as the standard TN Arms lower), and are probably closer to 4 oz now.

 

[packgoatguy]

Update on trying to plug the barrel gas hole... the JB weld and aluminum rings held for about 10 shots. I then tried adding a lot more JBweld around the edges, still using the aluminum rings... probably a good 1/8 inch thick of the epoxy around it. That failed in one shot. So I cleaned the jbweld all off to bare metal, removed the rings. I tried just installing a steel gasblock upside down, just to see what it would do. Still got leakage (put silicone around all the seams so I could tell). I was going to try to find a tap small enough to get a bolt in there, but then I found a tiny machine screw that was just skinny enough that I could get it to thread into the existing hole... so, I applied a bit if the 24hour 5k psi jbweld, on the screw and threaded it in. I used my borescope to make sure I didn't screw the bolt in too far. Then after that epoxy cured, cut the exposed head ic the screw off flush with the top of the barrel, and used jbweld to put a piece of aluminum tube back over it. So far this has held up for 12 rounds.

In hindsight, I should have just used a tap and put a real bolt in from the get go.

The good news is this faxon barrel is shooting awsome! Under MOA so far. Surprisingly easy to shoot. I'm glad I upgraded the trigger.

Still holding at 64.6oz not including the suppressor. 79.4oz including suppressor and tripod.

 

[packgoatguy]

Up to 20 shots now on this latest gas hole plug. Pic of 8 shots with cheap m855 62gr green tip ammo.

 

[Taudisio]

Update on trying to plug the barrel gas hole... the JB weld and aluminum rings held for about 10 shots. I then tried adding a lot more JBweld around the edges, still using the aluminum rings... probably a good 1/8 inch thick of the epoxy around it. That failed in one shot. So I cleaned the jbweld all off to bare metal, removed the rings. I tried just installing a steel gasblock upside down, just to see what it would do. Still got leakage (put silicone around all the seams so I could tell). I was going to try to find a tap small enough to get a bolt in there, but then I found a tiny machine screw that was just skinny enough that I could get it to thread into the existing hole... so, I applied a bit if the 24hour 5k psi jbweld, on the screw and threaded it in. I used my borescope to make sure I didn't screw the bolt in too far. Then after that epoxy cured, cut the exposed head ic the screw off flush with the top of the barrel, and used jbweld to put a piece of aluminum tube back over it. So far this has held up for 12 rounds.

In hindsight, I should have just used a tap and put a real bolt in from the get go.

The good news is this faxon barrel is shooting awsome! Under MOA so far. Surprisingly easy to shoot. I'm glad I upgraded the trigger.

Still holding at 64.6oz not including the suppressor. 79.4oz including suppressor and tripod.

I’m nervous about this happening with mine. I was reading on another thread, guys were just cutting and folding their gas tube so any carbon buildup would stay in the tube instead of the gas port. I was looking over about 10 noveske “chainsaws” and they all had gas leakage from the factory so I don’t feel so bad about it when I think of those.

 

[packgoatguy]

I’m nervous about this happening with mine. I was reading on another thread, guys were just cutting and folding their gas tube so any carbon buildup would stay in the tube instead of the gas port. I was looking over about 10 noveske “chainsaws” and they all had gas leakage from the factory so I don’t feel so bad about it when I think of those.

Interesting idea about trying to avoid some of the carbon buildup. However, just judging from what the pressure from my gas port has been able to blow through... I'm not sure if a folded aluminum tube will be up to the task without significant leakage. Plus, then you still have the ounce of gas block added.

 

[Thegman]

Update on trying to plug the barrel gas hole... the JB weld and aluminum rings held for about 10 shots. I then tried adding a lot more JBweld around the edges, still using the aluminum rings... probably a good 1/8 inch thick of the epoxy around it. That failed in one shot. So I cleaned the jbweld all off to bare metal, removed the rings. I tried just installing a steel gasblock upside down, just to see what it would do. Still got leakage (put silicone around all the seams so I could tell). I was going to try to find a tap small enough to get a bolt in there, but then I found a tiny machine screw that was just skinny enough that I could get it to thread into the existing hole... so, I applied a bit if the 24hour 5k psi jbweld, on the screw and threaded it in. I used my borescope to make sure I didn't screw the bolt in too far. Then after that epoxy cured, cut the exposed head ic the screw off flush with the top of the barrel, and used jbweld to put a piece of aluminum tube back over it. So far this has held up for 12 rounds.

In hindsight, I should have just used a tap and put a real bolt in from the get go.

The good news is this faxon barrel is shooting awsome! Under MOA so far. Surprisingly easy to shoot. I'm glad I upgraded the trigger.

Still holding at 64.6oz not including the suppressor. 79.4oz including suppressor and tripod.

I was wondering if this might happen. I know that even when I cut down an aluminum gas block too much, the pressure started moving the gas block. I do get a little leakage around some of my gas blocks, but it doesn't seem to hurt anything as long as they don't move.

Some barrels build up a copper plug from bullet jacket material and seal themselves under the block. A sleeve would probably work fine once so plugged, but not all barrels seem to do this. The plug can be cleanly blown out with a single shot without the gas block installed.

Your rifle looks like it's shooting great! AR platforms seem to shoot better than I'd have ever expected.

 

[packgoatguy]

I was wondering if this might happen. I know that even when I cut down an aluminum gas block too much, the pressure started moving the gas block. I do get a little leakage around some of my gas blocks, but it doesn't seem to hurt anything as long as they don't move.

Some barrels build up a copper plug from bullet jacket material and seal themselves under the block. A sleeve would probably work fine once so plugged, but not all barrels seem to do this. The plug can be cleanly blown out with a single shot without the gas block installed.

Your rifle looks like it's shooting great! AR platforms seem to shoot better than I'd have ever expected.

Accuracy with and without the hole leaking seems to be the same, but it does appear to lower the velocity about 50fps.