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Gunsmithing LRI 5x Blueprint on an FN/SPR
- Thread starter LRI
- Start date
Thanks for sharing that. Very cool to watch the multi-axis machines in use to compensate for angular irregularities.
Awesome video. Don’t see much fn/winney stuff. Might have to send my fn your way one day and have some work done.
Chad, with removing a few thousands of material off, it seems you're leaving the bare metal exposed. Is there a standard finish you apply on them? Or are these special ordered with a custom finish for your client?
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99.9% of our builds involve some sort of finish work after machining. The first op on all of this stuff is to run the receiver through the honing process to clean up the bores. That too removes a portion of the finish. We offer the usual suspects. Cerakote, parkerizing, bluing, anodize, DLC, nitride, glass bead, and color case. French gray is also something we do although I can't recall the last time anyone asked for it.
? Great videos Chad. Can really geek out watching these. Love me some claw actions. Most videos are pushfeed stuff, appreciate getting to see these done. Shoot M70’s for hunting and building a Mausingfield PRS rifle now.
Going to be a part 3 for the bolt?
Going to be a part 3 for the bolt?
I wish I would have grabbed a couple when CDNN blew them out for cheap. I was going to sell my SPR but I think I'll hang on to it and eventually rebarrel it to a more desirable caliber.
Put a price on it, pretty sure I'll buy it lol. It seems all i do now with being bored at home is buy buy buy.
Chad, will the M70/SPR action be barreled in 6br/dasher and run reliably? I have one that I'm toying on sending to you all for a barrel(and hopefully a DBM when you get yours done) and have it narrowed down to 6br, 6x47 or 6 5x47.
Watching how you program and making people figure out why should be a part of all CNC machining programs. It looks like you have your programs streamlined to knock out high quality work at high speed. Productivity and quality often dont go hand in hand. I feel you maybe driving the industry.
Watching how you program and making people figure out why should be a part of all CNC machining programs. It looks like you have your programs streamlined to knock out high quality work at high speed. Productivity and quality often dont go hand in hand. I feel you maybe driving the industry.
I had this kind of discussion just yesterday with Justin from ARC. As most are aware, the short/fat stuff is more problematic than long, tapered cartridges. The drama-free solution for these in a CRF setting is a staggered stack, center feed magazine. AI, ARC, whoever. The trick I find most helpful with CRF receivers is to get the magazine to let go of the cartridge sooner than later along the feed lips/forward stroke of the bolt. This is why the ARC magazine has noticeably shorter feedlips when compared to an AI. The idea is the shell pressure from the cartridge sitting below the one being loaded helps to push the case rim into the bolt face. In the perfect world, this is done before the bullet ever hits the feed ramp making for very fluid bolt manipulation.
The issue with staggered stack magazines (be it a detachable or integral box) on a short case is they typically hang onto the case a little longer. This creates a challenge as the bullet is almost always headed up the feed ramp which introduces yaw. -What goes up on one side must go down on the other. In that instance, the rim dips down, and it's easy for it to slip under the bolt circle. The bolt then slides over the top of the case body and jams into it just ahead of the web.
Hope this helps.
I built a 6.5 creedmoor a couple years ago using one of the old CDNN SPR receivers.
It's been my best rifle build yet. The bolt cycles / feeds slick as snot. It feels like the bolt has roller bearings. It's In a manners T4 stock, and inletted for the FN TBM bottom metal. I bushed the firing pin to .062" diameter, and worked on the stock trigger a little.
I chambered a Benchmark 4140 chromoly, 8 twist Sendero blank for it, finished @ 22". Scoped with a fixed 10x US Optics ST10.
I had a case of several thousand 140 Amax bullets, so that's what I've been shooting through it the entire time I've had it. Hornady brass, Winchester primers over 41.6 grains of H4350.
The gun started out shooting groups anywhere between 5/8" and 3/4", but over time it seems to shoot better and better.
I'm at about 1100 rounds now, and most groups are under a half inch @ 100 yards. Occasionally well under.
I shot my tightest group ever with it last week. 5 rounds @ 100 yards. The thin line grid is .1 mil.
It's too bad the supply of these receivers dried up. I'd love to have a few more.
It's been my best rifle build yet. The bolt cycles / feeds slick as snot. It feels like the bolt has roller bearings. It's In a manners T4 stock, and inletted for the FN TBM bottom metal. I bushed the firing pin to .062" diameter, and worked on the stock trigger a little.
I chambered a Benchmark 4140 chromoly, 8 twist Sendero blank for it, finished @ 22". Scoped with a fixed 10x US Optics ST10.
I had a case of several thousand 140 Amax bullets, so that's what I've been shooting through it the entire time I've had it. Hornady brass, Winchester primers over 41.6 grains of H4350.
The gun started out shooting groups anywhere between 5/8" and 3/4", but over time it seems to shoot better and better.
I'm at about 1100 rounds now, and most groups are under a half inch @ 100 yards. Occasionally well under.
I shot my tightest group ever with it last week. 5 rounds @ 100 yards. The thin line grid is .1 mil.
It's too bad the supply of these receivers dried up. I'd love to have a few more.
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Calling the FN SPR what it is: A rebadged M70 control round feed.
With that in mind, there was a time when the M70 held more records at Perry for Highpower than all other manufacturers combined. That has changed, but it wasn't all that long ago. -Late 90's.
A classic never dies.
With that in mind, there was a time when the M70 held more records at Perry for Highpower than all other manufacturers combined. That has changed, but it wasn't all that long ago. -Late 90's.
A classic never dies.
Lock time shouldn't be any different than a Rem 700 variant, they're both striker fired bolt actions right? There are fewer triggers available for the Win 70, but the stock Winchester 70 trigger is an excellent trigger- one of my main rifles I shoot in matches in an FN SPR action in 6.5 CM and I've been running the stock trigger since I got the rifle in 2010. I'll even go so far as to say I think the Win 70 factory trigger is one of the best and easiest to adjust single stage triggers out there.
No, the lock times vary quite a lot. Snap in a little with a match 700, and then go take a few shots with a Mauser or Arisaka. The difference will be apparent.
I see your point- I forgot about the Mauser or say the Springfield 1903 having longer lock times (I've never handled an Arisaka). I don't feel like the Win 70 lock time is longer than a Rem 700. Firing pin travel is very similar and I don't think the strikers have a huge weight difference between Rem 700 and Win 70. Plus like Chad said, the Win 70 used to be the king of match rifle across the course NRA Highpower competition and I don't think they would have won so much if the lock time was terrible.
I found this post on another forum that has list of lock times for various guns- according to this the Win 70 and Rem 700 have the same lock time.
www.hunttalk.com
Lock Times for Factory Rifles
Last summer, on the recommendation of BuzzH, I installed a Tubbs Speedlock firing pin assembly on my custom .260 Rem. At the time I basically understood the concept, but recently wanted to learn a bit more. So.....I have been on paternity leave for the last couple of weeks, and while my new...
www.hunttalk.com
Yeah, it used to be. The reason it doesn’t hold that many of our records now is because we are all shooting equally accurate rifles, but we have DBM and no bolt to run. At least for Course, it’s not even close. Sure, a REALLY good bolt gunner can keep up, but he sure as shit doesn’t have as much time to ponder sight picture, or solve the odd problem, as I do.
Yet the appeal of the M70 remains...
The locktime of even the fasted AR triggers is in the 4-5 ms time, which is pretty horrible, yet we shoot them pretty accurately.
I hear you... I started shooting Highpower with an M1 Garand in 1998. However, if you look at the winning scores, the match rifle winners are, using bolt guns, shooting higher scores than the service rifle guys shooting ARs. Having said that, since I got into precision rifle, I haven't shot NRA Highpower much, so I don't keep up with what that match rifle guys are using these days.
We call the rifles “SBMR”. That’s: Short Barreled Match Rifles.
They shoot 1/2 Minute, have no recoil in sitting, have less wind effect in offhand, maintain ~1/2 minute/mph at 600, and are allowed 4.5x scopes.
That’s what we call a “Service Rifle” now.
The rule changes have so narrowed the distance that you just don’t even see a Match Rifle that often.
They shoot 1/2 Minute, have no recoil in sitting, have less wind effect in offhand, maintain ~1/2 minute/mph at 600, and are allowed 4.5x scopes.
That’s what we call a “Service Rifle” now.
The rule changes have so narrowed the distance that you just don’t even see a Match Rifle that often.
It has to do with multiple work offsets being applied to various features. Dynamic work offsets work when using a single offset with rotated planes. I'm calling stuff out individually. Haas does not have a canned cycle to self orientate a part to a particular plane. You can rotate planes all day which is how you can literally slap a vise onto a table and not even worry about indicating it in (something I still cannot bring myself to do).
To my knowledge, nobody does. That was the real work; getting the macro syntax and trig functions to work predictably and reliably.
Many, many late hours. . .
One has to understand what I'm doing is not "making a part". That is far easier because you actually get to define where things go. Here, I am working with something existing and having to "find it" and rework it with a minimalist strategy always being at the forefront.
Great question.
We do it all the time with G68.2 (Tilted Working Plane) for 3+2, and G43.4 (Tool Tip Point Control) for full simultaneous 5 axis.
the machine needs to have a very good static alignment and good pitch comp tables to be accurate in doing it, but that all we use, for everything from farm equipment to aerospace parts.
Are you making a part from scratch, or essentially reworking parts that have been made for the last 50, 60 years? For instance, if you assume that an M700 thread start position is the same on every action, you're going to get good at scrapping parts. If you assume that all receivers have a 1.150" face to lug abutment length (the correct nominal length) you're going to find yourself headspacing guns off the bolt handle because in some instances the lugs won't be even touching the receiver in battery.
I'm much more at home with running an additional probe cycle to ensure I know exactly where my position is vs relying on software to do it for me.
