Ultralight Ultralight Rifles

[grappling_hook]

I mentioned drop testing a few posts back.

Did some drop testing today with the Primary Arms SLx 5x MicroPrism on my ultralight AR setup and recorded my process. Results: https://rokslide.com/forums/threads/quick-dirty-drop-test-primary-arms-slx-5x-microprism.398996/

 

[Luke S]

That is cool to see it pass that. I'd be tempted to try one of those.

I forgot to take a picture but I got my rifle down to 3 pounds 6 oz with a Farrow Tech butt on an A2. Nice but I think I'll return the butt plate and swap it for a slightly heavier one. I want to be able to make the LOP just a tad shorter. Until then I'll keep using the CAR 15 style collapsible stock.

 

[Trackselk]

I had another idea that might work to get the NAS3 cases to work in the strait-pull config. AI chamber... After some measuring I figured out that the reason for them jamming the action is that the shoulders are out of spec. This effectively makes them have zero headspace, and then they create pressure against the bolt face after being fired.
From what I've read, full power 223&5.56 rounds shoot well in a 223AI chamber.

So, is anyone here with a strait-pull willing to fire a few factory Phantom Wasabi rounds if I mail them to you? The out of spec that I'm talking about is literally a difference of about 1 thousandth, and a tap on the bolt handle with a rubber mallet, stick, boot etc. Not terrible, but not satisfactory either. So, it won't hurt your rifle, especially if you lightly grease the lugs. Avoid oil and grease on the bolt face though, as that'll just make it even tighter, and give us false readings. Clean bolt face first.
I'm even optimistic that we can get a second loading out of them with neck sizing. Once I verify that they work once, I'll order a neck sizer and get a chamber reamed for AI.
Probably need to tweak the charge after they are fireformed, but I've read of instances where people used the same charge. Either way, I'll be happy with 1 or 2 firings, as the cases are not very expensive for a low volume hunting rifle. Shoot bulk for practice...

 

[Taudisio]

I had another idea that might work to get the NAS3 cases to work in the strait-pull config. AI chamber... After some measuring I figured out that the reason for them jamming the action is that the shoulders are out of spec. This effectively makes them have zero headspace, and then they create pressure against the bolt face after being fired.
From what I've read, full power 223&5.56 rounds shoot well in a 223AI chamber.

So, is anyone here with a strait-pull willing to fire a few factory Phantom Wasabi rounds if I mail them to you? The out of spec that I'm talking about is literally a difference of about 1 thousandth, and a tap on the bolt handle with a rubber mallet, stick, boot etc. Not terrible, but not satisfactory either. So, it won't hurt your rifle, especially if you lightly grease the lugs. Avoid oil and grease on the bolt face though, as that'll just make it even tighter, and give us false readings. Clean bolt face first.
I'm even optimistic that we can get a second loading out of them with neck sizing. Once I verify that they work once, I'll order a neck sizer and get a chamber reamed for AI.
Probably need to tweak the charge after they are fireformed, but I've read of instances where people used the same charge. Either way, I'll be happy with 1 or 2 firings, as the cases are not very expensive for a low volume hunting rifle. Shoot bulk for practice...

@C Bow ??????

 

[hereinaz]

I had another idea that might work to get the NAS3 cases to work in the strait-pull config. AI chamber... After some measuring I figured out that the reason for them jamming the action is that the shoulders are out of spec. This effectively makes them have zero headspace, and then they create pressure against the bolt face after being fired.
From what I've read, full power 223&5.56 rounds shoot well in a 223AI chamber.

So, is anyone here with a strait-pull willing to fire a few factory Phantom Wasabi rounds if I mail them to you? The out of spec that I'm talking about is literally a difference of about 1 thousandth, and a tap on the bolt handle with a rubber mallet, stick, boot etc. Not terrible, but not satisfactory either. So, it won't hurt your rifle, especially if you lightly grease the lugs. Avoid oil and grease on the bolt face though, as that'll just make it even tighter, and give us false readings. Clean bolt face first.
I'm even optimistic that we can get a second loading out of them with neck sizing. Once I verify that they work once, I'll order a neck sizer and get a chamber reamed for AI.
Probably need to tweak the charge after they are fireformed, but I've read of instances where people used the same charge. Either way, I'll be happy with 1 or 2 firings, as the cases are not very expensive for a low volume hunting rifle. Shoot bulk for practice...

The AI has less taper generally making extraction a little more difficult, no? Would you possibly be changing one problem for another?

 

[Trackselk]

The AI has less taper generally making extraction a little more difficult, no? Would you possibly be changing one problem for another?

I'm not sure, looked like it might just have one tiny area to hang up on?

 

[hereinaz]

I am saying

I'm not sure, looked like it might just have one tiny area to hang up on

The greater taper makes it easier to extract because of the shape is smaller as you go forward. Maybe I am mistaken, but doesn’t the AI blows out that taper and changes the angle of the shoulder?

 

[Taudisio]

I am saying


The greater taper makes it easier to extract because of the shape is smaller as you go forward. Maybe I am mistaken, but doesn’t the AI blows out that taper and changes the angle of the shoulder?

I am not well versed in the 223ai, but I know the 280ai is less tapered. But I don’t think we have a definitive answer on what exactly makes the cases sticky do we? Just assumptions right?

 

[C Bow]

I would be happy to try a few for you but my barrel is not back yet hoping to get it in next couple weeks. When it get here I will let you know

 

[Thegman]

I would be happy to try a few for you but my barrel is not back yet hoping to get it in next couple weeks. When it get here I will let you know

Are you getting a 223 AI barrel? That will be interesting if so. I'm thinking a 223 AI barrel throated for 75 and 80 ELDs to shoot decently at 2.36" would be pretty interesting to try.

The lack of taper probably won't be an issue for extraction. 300 HAM’R is pretty much an AI 30 caliber and it works very well. I think the issue with sticking is probably increased thrust from larger case heads.

The potential issue I see is AI-ing a chamber without any set back of headspace. It may not work very well with regular 223 ammo without being set back just a bit. I think otherwise the headspace may be increased slightly.

FWIW, I haven't shot any of the NAS cases yet, but they chamber fine in my Shaw. I'll check them with the BCA barrel and see. One thing you might try is swapping a few different bolts. I've had to do that with one of my HAM’R barrels to find a tighter headspace bolt. It's chamber was loose enough that primers were pushing out a little when using brass sized for my other HAM’R barrels. It's headspace just happened to be at the far end of chamber tolerances. Your 223 barrel-bolt combination might be at the short end of the same (??).

 

[Thegman]

I am saying


The greater taper makes it easier to extract because of the shape is smaller as you go forward. Maybe I am mistaken, but doesn’t the AI blows out that taper and changes the angle of the shoulder?

Any updates on the barrel project you've been working on?

 

[C Bow]

Any updates on the barrel project you've been working on?

Going to go by this weekend and check He told me he would try his best to have by end of month. The barrel I am using for this is a Shaw 223 Wylde

 

[ezwy]

I'm not sure, looked like it might just have one tiny area to hang up on?

Do you think the NAS3 cases will fire form to the ackley chamber?
I have shot the phantom wasabi’s out of my Shaw 223 wyld. They are a bugger to extract, but shoot fast and accurate. I did have holes in a couple primers.

 

[Trackselk]

I am not well versed in the 223ai, but I know the 280ai is less tapered. But I don’t think we have a definitive answer on what exactly makes the cases sticky do we? Just assumptions right?

I think I narrowed it down to the shoulder angle on the NAS3 cases. It was when I put them in a 223 case gauge that it was obvious, as the head protruded .001" above max Sammi.
@hereinaz, I think it's like you said, and then like thegman said, the loose chamber issue is actually going to give the nas3 cases the extra thou or 2 that they need. They may still swell up and not bounce back enough, and thereby keep pressure on the bolt face, which makes it difficult to disengage the (lugs?). I don't know if this is what's happening on the bigger caliber cases, but I'm 99% sure that's the problem with the nas3 cases.
-With the 223ai chamber, 3000 fps 77grain bullets will be easily under 70k psi if I'm not mistaken, and these cases are rated for 80k. Should be very safe, and I might creep up slightly more if it lands me in an accuracy node.
Basically 200fps faster than the lever powder recipe with cases that make it much safer, have greater neck consistency, bigger flash hole, 10% capacity. But, if these cases ultimately fail, I'll run the lever recipe at 28-2900 in an ai chamber, but it won't be as safe. I might even get crazy and take the nas3 cases up to 3100 fps, but only if I can't find a node between 2900&3k.

 

[Trackselk]

Do you think the NAS3 cases will fire form to the ackley chamber?
I have shot the phantom wasabi’s out of my Shaw 223 wyld. They are a bugger to extract, but shoot fast and accurate. I did have holes in a couple primers.

Yes, they definitely will, and if they still extract well, it might be easy to get 3100 fps+, barrel dependent. Still going to be way under the 80k psi.
But, they might wedge themselves in there on the 2nd firing, but worth a try. Would cut the cost in half for the cases if we got 2 loadings. Probably a waste of time if the charge needs adjustment for the formed case, unless someone really wants yet a bit more speed. I'd probably only go to that extent if I was chasing the next accuracy node
Edit: I should add that this all may be playing with fire with our slight profile barrels, but if the nas3 cases are legitimately able to handle 80k, then maybe it isn't a big deal. I'll probably keep them in the 3k fps area since they are so new. Let someone else learn where the too hot zone is. I do have one source that's a manufacturer, and they said they didn't blow up a barrel until 110+psi with the nas3 cases, but they weren't likely shooting a noodle profile...

 

[Trackselk]

I would be happy to try a few for you but my barrel is not back yet hoping to get it in next couple weeks. When it get here I will let you know

Sounds good, thanks! I might figure it out by then, but I talk with a couple of local gunsmiths tomorrow to find out if they have an ai reamer, and can throat it long, and don't want an arm and a leg. I was going to buy a uni- throater and throat my own before I decided to chase this AI idea.