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Introducing Rubin - StoneHendge - 03-15-2021
In commemoration of my 100th post, the time has come to introduce Rubin. A project 3.5 years in the making which has been undergoing a super top secret completion the past couple of weeks has come to fruition. Because no one thought I could leave a Lilja 6 ARC barrel waiting in the back corner of the closet, did they?
Rubin is the runt of the Hendge household, weighing in at 5.15 lbs unscoped and 6.67 lbs with my trusty old Vortex HSLR 2.5-10x30 FFP (XLR Reticle) sitting up top. All that's missing is gas block, gas tube and crush washer, so his weight will go up a smidgen. But he's ready to test fire after I made 5 ARC cases yesterday so I can get a headspace reading and properly size when I go into mass brass production.
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Gigi isn't jealous at all. If fact, they make a cute couple for a skinny guy and a heavy set girl.
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There may be some jealousy on match days in the future, but we will cross that bridge when it's time.
Build details to come......
RE: Introducing Rubin - SBRSarge - 03-15-2021
It’s nice of you to give Gigi some company, don’t want her feeling unloved!
RE: Introducing Rubin - SvenGar58 - 03-15-2021
Very nice work. I’ll not be so presumptuous to ask you to explain, but I’ll admit I’m curious about your gun naming convention.
RE: Introducing Rubin - StoneHendge - 03-15-2021
(03-15-2021, 02:03 AM)SvenGar58 Wrote: Very nice work. I’ll not be so presumptuous to ask you to explain, but I’ll admit I’m curious about your gun naming convention.
Most require at least a beer to explain. Except for Drogon (my 6.5CM). Either you get it or you don't.....
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RE: Introducing Rubin - SvenGar58 - 03-15-2021
(03-15-2021, 04:38 AM)StoneHendge Wrote:A beer is a small price to pay for an interesting bit like that. I'd pay a good single malt for the explanation if we were anywhere near enough to get together to discuss it. Unfortunately, I'm a long way from everywhere, so I'll just have to wonder. In any event, congrats on the new build. I'll have to think about how to name mine. Boats are easier to name for lots of reasons in my experience, but I'll not go into that in this venue.(03-15-2021, 02:03 AM)SvenGar58 Wrote: Very nice work. I’ll not be so presumptuous to ask you to explain, but I’ll admit I’m curious about your gun naming convention.
Most require at least a beer to explain. Except for Drogon (my 6.5CM). Either you get it or you don't.....
RE: Introducing Rubin - Old Bob - 03-15-2021
Currently, mine are named 1 of 6, 2 of 6, 3 of 6 ... etc ... If I build another AR I'll have to change their names again.
RE: Introducing Rubin - SvenGar58 - 03-17-2021
(03-15-2021, 01:28 PM)Old Bob Wrote: Currently, mine are named 1 of 6, 2 of 6, 3 of 6 ... etc ... If I build another AR I'll have to change their names again.If you'd thought a bit more when you started -- which none of us ever do with guns, fly rods, or significant others -- you might have named them 1 of X, 2 of X, 3 of X, etc. Then you would never have to change their names! Just think, 1,539 of X!! The possibilities are endless.
RE: Introducing Rubin - StoneHendge - 03-17-2021
What do you guys put in your ballistics app. Seriously.
[attachment=194]
Note: Given the current political environment, I should note that almost all of these rifles were recently lost in a freak boating accident.
RE: Introducing Rubin - SvenGar58 - 03-17-2021
(03-17-2021, 03:03 AM)StoneHendge Wrote: What do you guys put in your ballistics app. Seriously.I just went looking and discovered that none of mine seem to be anywhere in the house!! Must have been stolen!!
Note: Given the current political environment, I should note that almost all of these rifles were recently lost in a freak boating accident.
In any event, I'm working on names. The first serious pistol I acquired is called Eargeshplitenloudenboomer. I'll not trouble you with the original German from which that is translated.
RE: Introducing Rubin - StoneHendge - 03-17-2021
(03-17-2021, 03:48 AM)SvenGar58 Wrote:That pistol just have impressed die fraulein mit die grosse bombe!(03-17-2021, 03:03 AM)StoneHendge Wrote: What do you guys put in your ballistics app. Seriously.I just went looking and discovered that none of mine seem to be anywhere in the house!! Must have been stolen!!
Note: Given the current political environment, I should note that almost all of these rifles were recently lost in a freak boating accident.
In any event, I'm working on names. The first serious pistol I acquired is called Eargeshplitenloudenboomer. I'll not trouble you with the original German from which that is translated.
RE: Introducing Rubin - SvenGar58 - 03-17-2021
(03-17-2021, 04:01 AM)StoneHendge Wrote:Die Frau. Not that I mean to be pedantic regarding German grammar, but my wife is my wife, after all.(03-17-2021, 03:48 AM)SvenGar58 Wrote:That pistol just have impressed die fraulein mit die grosse bombe!(03-17-2021, 03:03 AM)StoneHendge Wrote: What do you guys put in your ballistics app. Seriously.I just went looking and discovered that none of mine seem to be anywhere in the house!! Must have been stolen!!
Note: Given the current political environment, I should note that almost all of these rifles were recently lost in a freak boating accident.
In any event, I'm working on names. The first serious pistol I acquired is called Eargeshplitenloudenboomer. I'll not trouble you with the original German from which that is translated.
RE: Introducing Rubin - StoneHendge - 03-17-2021
Gas block iis allegedly out for delivery today. Range time booked for tomorrow.
Those who know me from the 6.5G forum may know I have a fetish for putting nonprecision ammo in plastic baggies. Since I only have 5, I put it in a dime baggie.
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RE: Introducing Rubin - StoneHendge - 03-19-2021
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He's done and even better, he works! Final tally on the scale is 6.84 lbs scoped. And that includes the pig sized Sadlak clamp on gas block which tips the scale at 1.9 oz instead of the 1.1 oz Faxon lightweight block I wanted to use. Basically, the gas block journal is too big - measures in at .754" while the Faxon is 0.753". It scraped my Duracoat (in a rattle can) off trying to get the Faxon on and could only get it up halfway. I'm sure that Rebby and Lilja would have taken care of it, but that would be a PIA and require patience. So I figured I could get a clamp on up there (which I like better anyways) and a Sadlak (makers of quality AR parts since ....... I don't know when - I've never heard of them!) was all I could find.
Felt recoil with a light charge and a 90 grain Sierra FMJ was quite a bit more than GiGi's 95 gr TMK load, but that should be expected. The good news is that the 2A Armament Ti Bolt Carrier really does its job. Return to battery is where I always get moved a little off target for follow ups and the decreased mass really helps. I don't think the return to battery dip is any worse than with GiGi and her JP Low Mass carrier.
Head space with a Maxim bolt with the Lilja barrel is perfect. Sized my 5 pieces of brass down to SAAMI minimum. 1.183 base to B comparator line and they came out at 1.188.
Now I just need to decide which Starline brass he gets - the nickel or the ordinary - and then lube up the trimmer.
- Actually, he's not quite done - a JP thermal dissipator is likely in the cards. Which will unfortunately put him a tad over 7lbs, but he will likely see up to 20 rounds in 90 seconds if I use him for my "Accurized AR Match". Planning for the dissipator made the decision to go with the Odin O2 Lite easy since a dissapator wouldn't fit under most of the other super lightweight options out there (excluding carbon fiber, which I didn't view as an option given its insulating properties and likelyhood that it would get extremely scuffed up getting rested on props, rocks, etc.)
RE: Introducing Rubin - StoneHendge - 03-19-2021
I think Rubin might have the purtiest 6 ARC brass on the planet.
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RE: Introducing Rubin - SvenGar58 - 03-20-2021
(03-17-2021, 05:11 PM)StoneHendge Wrote: Gas block iis allegedly out for delivery today. Range time booked for tomorrow."Range time booked for tomorrow." Wow! I'm 5 minutes from the rifle/pistol range. This time of year, I can go out there at 0700 - 0800 and have it all to myself. Ir's free and uncontrolled; I've never had to book time on the range like I did on the golf course a long time ago. I am blessed to be in a far away place from a time long ago.
Those who know me from the 6.5G forum may know I have a fetish for putting nonprecision ammo in plastic baggies. Since I only have 5, I put it in a dime baggie.
RE: Introducing Rubin - StoneHendge - 03-21-2021
I think I'm really going to like this barrel. Loaded up 50 of the 90 gr Sierra FMJs with 29 grains (+/- 0.1) of CFE and did some fireforming today. When I did the 5 shots a few days ago, I was sighting in another rifle and took all five shots from Rubin at 25 yards and had the last one an inch low nearly on the center vertical line - so it's not zeroed but is seemingly close. Went prone with 10 rounds and once I figured out the vertical hold, I was actually able to get down to the 4"er on a TYL rack at about 280. The remaining 40 were mostly hits on a spinner at 300 with 8" and 6" rounds mostly kneeling with the only support being my handguard on a Whiskey Charlie Max on a stool, so work some wobble into the equation. In some ways, it's actually easier to stabilize a really light rifle - just feels easier to wrap my thumb around the handguard at the end and pull the rifle and bag (with lower fingers) into my shoulder and magwell/mag. Anyways, getting all those hits on 2 MOA target at 300 with a random load and unbroken in barrel was pretty encouraging (and I'll add that the Sierra 90s didn't shoot well in my 6x45, which is why I bought them).
Dialed down the gas significantly and felt recoil was substantially reduced. The Ti carrier has an adjustable gas key and it's been a question mark if I can get it to cycle reliably with a reduced power spring and Taccom Ultralight carbine buffer (both the carrier and buffer are "recommended for use with .223/5.56 only"), but so far so good. It didn''t make neat little piles of brass like GiGi and Nozzie were today, but I need to bring stronger reading glasses next time so I can see the adjustment screw better. You can see the adjustment screw on the BCG. It's the left screw (the top screw holds it in place). Vertical is full open and horizontal is fully shut, so it's actually a tad below 50%. The little tool fits easily in a grip storage compartment.
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50 more pieces of brass to make and fireform this week while finishing break in, and then it will be time to crack open a fresh keg of Varget and get to work with some105 gr RDFs.
RE: Introducing Rubin - StoneHendge - 04-03-2021
I believe we have a load. Varget and 105 gr RDFs were the hope and it looks like it will work quite well. 2500 fps was the target and it looks like it will fall a bit short at 2450. Nothing that that's going to impress any hunters around here, but at today's density altitude of 4050 ft at 90 degrees (spring is here!), the RDF and its 0.280 G7 will start transitioning around 920 yards and stay supersonic to 1125. From a 6.84 lb carbine with a 16" barrel and a 37" OAL with the stock fully extended. Falling short 50fps cost about 35 yards.
The weight clearly magnifies shooter error. Go soft on the shoulder? Grip too tight? Go inconsistent on the bipod? Have a brainfart while pulling the trigger? You'll see it downrange. The weight also results in more felt recoil, but it feels deep and smooth. Return to battery (which is what throws me more off target) is very light with the Ti carrier and results in not much more than a twitch in my sight picture. Learning to handle this rifle is going to make me a better shooter - unforgiving, but a scalpel in the right hands. It's reminiscent of old Porsche 911s - where you actually had to know what you were doing to drive one fast.
In my initial ladder, 26.8 gr gave me 2448 with an sd of 6. Sd was 8 at 27.0 and both had good accuracy so I loaded up 31 at 26.9 for today. One fouler then 10 over Magnetto which gave me 2455 with an sd of 10. I'll probably drop back to 26.8.
The remaining 20 were shot in four five shot groups. This isn't the best of the groups - it's all of them. The first set is bottom left and I went clockwise. The first 2 were on my Atlas bipod with a rear bag on a slippery concrete bench. The bipod slipped on one shot in the first group (circled). Annoyed with the bench, I went prone (where the concrete is still slippery (give me dirt and I don't need no stinking mat!)). I forgot to load the bipod on the first shot (circled) and reached deep into the depths of my being to concentrate hardest on the last and best group. I'll take an average of 0.94 MOA which includes shooter error and 0.78 MOA if I exclude the obvious errors - this is from a 6.84 lb carbine with a 28 ounce barrel and was shots #143-162 (so it's probably still breaking in a bit). It looks like I need to move the zero a click left, but I like that 7 of the 20 are touching the aiming dot. I haven't actually zeroed it - I just made some adjustments based upon where the Magnetto shots went and it looks like I got damn close. The little barrel heats up but there was no drift of the zero (have I mentioned how much I love Varget?). This is the internet after all, which is populated with thousands of images of tiny little groups - which are almost never clustered around the aiming point.
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Off to the steel range on Sunday where I can go to 550. Fun fact: 700 yard wind drift of this load is 42% less than a 77 gr Sierra TMK launched at 2700 - which would be a hot load out of a 20" .223. From a ballistic standpoint, it almost entirely matches up to what I did with 123 gr Scenars at 2560 out of my 22" 6.5 Grendel - using CFE.
RE: Introducing Rubin - StoneHendge - 04-05-2021
Well, I managed to get 10 rounds downrange before my session was abruptly ended. Everything was spot on out to 400 meters and then the 2 Japanese guys next to me who spoke broken english decided to try some of the .308 ammo they bought on GunBroker. It was packed loose in a 30 cal can with the old Federal XM193 label. It was old, tarnished, and about 90% of them had orange tips. Yup! They claimed they didn't know what it was.....
https://www.azcentral.com/story/news/local/arizona-wildfires/2021/04/04/bullet-ricochet-starts-brush-fire-behind-ben-avery-shooting-facility/7086079002/
You can see the spinner I was working in at 400 meters in front of the firetrucks.
I don't know if it's good or bad for PR that they say it was a ricochet. It is illegal to shoot a tracer anywhere in the State of Arizona (for good reason!), let alone a state run range.
They kindly refunded the range fee and it's back on Wednesday.
RE: Introducing Rubin - StoneHendge - 04-08-2021
Range sessions can be much more productive when people don't shoot tracers and start fires. And also when the concrete isn't slippery and your bipod doesn't move when you load it. Picked up where I left off this morning. One shot each at 200, 300, and 400 meters and everything was spot on. The TYL rack at 500 meters was freshly painted and no one had worked it, so why not! Held right edge on the 18" to get a solid read on the wind and then it was dead center on each shot at 12", 8"and 6" with a reticle elevation hold. Well maybe not dead center, but the 8" and 6" were no more than 1" from center. So that advertised G7 of .280 for the 105 RDF is spot on this far. I'm also guessing that if Rubin was put in some sort of bench rest rig and manned by someone who is actually halfway decent at shooting paper, he would shoot 1/2 MOA all day long.
Not to be outdone by her safe mate, GiGi proceeded to put her shots right on top of Rubin's - the 6" looked like one splatter.
Ave velocity was 2446 vs 2448 when I last Magnetto'd 26.8 grains and the temp was 9 degrees cooler, so pretty much in line with what one would expect from Varget. Hoping to get to a range south of town in the desert next week where they allegedly have permanent steel from 700 to 1100. I don't know if they are swingers or static and if they are backed by berms, but it's worth checking out and hopefully confirm that my little 6.84 lb carbine is indeed an 1100 yarder.
My biggest concern with a 3 groove 7 twist barrel is/was possible bullet deformation since not only is the RPM relatively high, but that each groove would place a higher incidence of lateral force on the jacket with only 3 of them. So far, so good. Although there may be something that manifests itself further downrange, I find it hard to believe it wouldn't cause some sort of increased dispersion at 550.
RE: Introducing Rubin - StoneHendge - 04-17-2021
Since GiGi is being such a b!tch, she's getting sidelined and Rubin will get the match call for next weekend. Got 40 more rounds of the 105 RDFs downrange including a fast paced 10 back and forth at 400 and 500 meters. I didn't notice any thermal drift, the operating system held up fine and all of the brass actually went to pretty much the same area. It defies the consensus logic, but it isnt hard to stabilize such a light rifle with the handguard on a bag on a barrier, and I was able to watch all of my impacts at various kneeling and standing heightds. Zero stayed zero (thumbs up this far for the Warne Skeltized Mount). Didn't chrono again, but the dope off of my Kestrel put it exactly where it was supposed to go.