The Creedmoor Forum

That's beautiful country Bob!

We segued into horses back around 1999 or so, lasted until 2008 when we moved back to the city where it became impractical to enjoy their company.

One horse in particular, a Tennessee Walker I named Kismet, was special to me. That gelding taught me a lot about myself. I'd ride him bareback to lunch at an orchard fruit stand, and let him mow their grass area untied. I'd have passing-through city folk ask me of I'm worried he'll run off, lol. Anyway, I'd finish lunch, grab hold of his halter rope, jump on his back and mosey home.

They weren't all like Kismet though, had a one or two that figured killing me was Job 1.

Our Dogwood is looking special this spring 

Quote from: DHuffman on April 16, 2024, 09:40:22 PMA bunch of the BR guys got their undies in a bunch about it last summer.

I've shot beside some pretty annoying or worse brakes competing. You either complain or time your shot so you break yours right after theirs. Not that complicated.
I know of a match where they put the braked guns in their own relay. Whatever I guess but it's getting ridiculous.

The claim, in this case, is less about affecting other shooters, it's more about the effect on you, yourself, shooting a muzzle-braked rifle on yourself. I'm not sure I'm buying the line.

Nothing against suppressors, I own several, but they come with their own set of issues, like holding acrid gas in the barrel which may leave the action from the chamber, closer to my nose than not.

I'm not convinced muzzle brakes are a personal risk; I do believe they may be unpleasant, annoying and distracting for adjacent shooters. The range where I shoot urges members with braked rifles to shoot on the last 5 benches; no problem.

I chatted with a fellow shooter and range member yesterday while I was on RSO duty. I've known him for years, and served RSO duty with him many times. This guy is very intelligent, a commercial international pilot by trade, and a serious competitive shooter.

I think because he knows I shoot with a brake, he dove into the risks of brain damage caused by the repeated concussive blast from muzzle brakes. He no longer will use a brake, nor flash hider; it's either no muzzle device or a suppressor. It didn't seem to matter when I explained that the shooter, myself in this case, doesn't feel the concussive blast, it's the folks on the sides, or standing behind the shooter that feel the blast, I say this because I've been the guy standing behind braked shooters.

In any event, this fellow shooter urged me to reconsider using a brake, I have no reason to believe his advice is anything but genuine, and given because he cares about me as friend.

I did an internet search on the matter and found several articles that appear to confirm what my friend told me. That said, I don't shoot 100s or 1000s of rounds on a regular basis, like military members may be required to do. Anyway, below is a link to one person's viewpoint on this which appears in-sync with what my friend stated.

Brain Drain

What do you guys think?

You ever have "one of those days"?

I felt as if the rifle was fighting me, just could not get a dead-steady hold on the target. Turns out the picatinny rail mounted Atlas bipod had come loose which rendered the cant control useless. I finally discovered this before the last group and did my best to fix it, more work needed.

Meteorologically, the weather was unstable, very windy, rain, sunshine, 45F or so ambient temperature.

Excuses aside, the target is the final arbiter, could've been worse 

From a mission standpoint, I don't feel that turning these necks outside and inside made a mess of things, nor do I see fame and fortune in my future, lol. I did learn not to take adjustable components like a bipod for granted that, just because I locked it in once, it will stay like that forever, that was chump on my part.


 

Got this batch ready for tomorrow.

From what I can tell, both with seating feel and gage equipment, annealing the brass smoothed things out. Not earth-shattering but the number of cartridges inside 1 standard deviation of seating Work increased to 25 out of 34 from 21 out of 35. Plus, I did not lube these necks, nor the bullets.

I didn't post the target from the first firing because I changed way too many things; new muzzle brake, new rear rest, I was an on-duty RSO, etc. We are allowed to shoot if things are slow, which was the case. I spent more time adjusting scope turrets than shooting  . In any event, the largest measured 5-shot group at 300 yards was .84 MOA, the best was .34 MOA.

I'm on-duty tomorrow, I'll see how this first reload looks if things stay quiet.

Quote from: gman47564 on April 10, 2024, 04:57:48 AMChris are you using the same instrument to measure with as you did to start with.. I know you been doing alot of experiments with measuring devices?

Grant, I did use the same micrometer when I turned both the OD-only and the ID/OD brass sets. that mic was not modified.

The modified mic indicates the ID/OD turned brass is 12.5 thou thick, as did the unmodified mic, this makes sense since both OD and ID turning were done on a trued mandrel and a trued socket-type mandrel respectively, I expected coaxiality.

Life has twists that keep me from shooting, but, I'm persistent darn it 

I shot the brass I'd posted about previously; necks outside and inside turned to 12.5 thou wall thickness. These necks look pretty clean which isn't too far off from how the last batch of outside turned necks looked when they were first fired; they were turned to the same wall thickness, 12.5 thou-ish.

The reason I'm posting this is I'm measuring the now-retired, 14x fired brass necks, they are averaging 11.7 to 12.0 or so neck wall thickness.

Do neck walls shrink in thickness as they're shot?

Quote from: autoxforfun on March 31, 2024, 11:13:46 PMDid you post a YouTube Video of the operation?

I have not, never tried posting to YouTube, don't even have an account, I probably should signup and try it one of these days.

Here's a close up of the parts and pieces:



The first part to address is the Spindle Gap Truing Grubscrew, upper left side. This tiny screw is designed to take up any gap between the spindle and body of the micrometer, a lucky person would have two spindles of the exact same diameter to work with, I was not lucky. The grubscrew must be adjusted to ensure a tight radial fit while allowing the spindle full axial travel; it's tiny, Mr. Magoo readers required  .

The digit counter drive wheel grubscrew locks the wheel to the shaft somehow so that it spins the counter when the spindle is turned while allowing for the spindle's axial movement. This part is a bit of a mystery to me, my understanding of it is anecdotal at this point.

The real trick, if having the vernier read zero when the mic is fully closed is desirable, is to separate the ratchet assembly from the thimble. These two assemblies are taper fit; after removing the ratchet screw a light tap with a rubber mallet frees the tapered parts. From there, it's simply a matter of closing the spindle to zero, rotate the thimble to zero, then reseat the tapered parts and secure the ratchet screw.

Setting the digit counter to zero is easy, especially if the person mad enough to attempt this is blessed with 3 hands  . Remove the two faceplate screws, loosen the counter screws, let it drop down so the digit wheel may be manually turned to bring the 4 digits to zero, push the counter back to engage the spindle wheel with the counter wheel, tighten the counter screws. Do this 10 or so times until the correct pair of amazingly small teeth are engaged, extreme patience and advanced anger management required, lol.

Never willing to leave well enough alone, I made a Franken-Mic 


Mitutoyo offers standard outside mics with flat anvils and flat spindles, tube mics with flat spindles and spherical post anvils, and inside mics with spherical spindles and anvils. The problem is the last variant is not offered with a spherical post anvil; the offered anvils will not fit inside a case neck.

So, what to do? The spherical tipped mics are more rare, and more expensive, I found a nice used one on eBay. My thought was to play a TV doctor and transplant the spherical spindle onto my tube mic which has the spherical post anvil. What could possibly go wrong?

Here's a post-surgery picture of the mic:



Tell you what, there's a lot going on inside a Mitutoyo mic but, I got it done after watching 3 YouTube vids.
   

That looks real good Bob, I may reclaim that Hornady gage I donated which no one uses 

I received and checked out the spherical spindle tip today; well worth $20 IMO.

My first impression was not good; the tip is not a tight fit on the spindle, that's when I connected the dots, it's not supposed to be a tight fit. The important thing is that the captured, precision ball bearing is allowed to rest on the flat face of the spindle on one end, while contacting the measured surface on the other end. Furthermore, a ratchet spindle is designed to apply just enough force to positively contact the measured surface without deforming said surface, the radial force of a tight fit may interfere with this delicate balance.

That said, the fitment area is split, presumably to accommodated small differences in spindle diameter. Here's a picture.



The piece of brass in the following pictures was outside mandrel turned on a lathe to 12.5 thou, the spindle tip adds 0.200 to the indicated dimension; it is right on. This micrometer tip allows me to examine thickness in the middle, towards the mouth and closer to the shoulder junction. It's not a donut hunter.







Noteworthy IMO, is the tilt in the piece of brass as it's being measured in the middle where it's plumb, tilted slightly counterclockwise as the shoulder is approached, and slightly clockwise as the mouth is approached. I think that's just center of gravity, not spindle-anvil alignment issues, I would've tried to keep them plumb but, I ran out of arms, lol. That's the beauty of spherical tips, they offer a degree of freedom  from perfect axial alignment.
 

I'm posting this only to alert others to shop around, buying direct from a retailer may not get you the best price.

I can purchase the Starrett anvil tip I posted about earlier directly from MSC Industrial, price is $19.11, sales tax $2.79, shipping $12.99, total $34.89.

Or, I can purchase the same item from MSC Industrial on their eBay store for $19.11, sales tax $1.66, shipping $0, total $20.77.

So, it would cost me $14.12 more to buy it directly from MSC  . I realize that's not even Big Mac money these days but hey, now that I'm retired, every dime counts. What I find astonishing is they ship items for free when sold on eBay where they have to incur seller transaction fees, I wonder how long they can sustain that business model?

As long as you get close enough to see powder burns in the haircoat, you'll be fine 

Quote from: jvw2008 on March 22, 2024, 01:58:43 PMLOL I don't think it has to be THAT sharp.

A point tip might be easiest to make on a mill. The ball is probably better using a lathe. Simply my guess based on very limited experience.

You're onto something Jerry, when turning a point on the lathe, it doesn't have to end in a point, it could be a 1mm or so flat. Then finish it up with sandpaper so any sharp edges are removed. I like it  .