Neck turning for success.

[Larry Koch]

We all build little motorized gizmos and gear reduction seems to be the part that has driven me nuts the most, until I found out about these Alpha industrial surplus reducers. They come in 050 size about the size of a baseball and good for 1/8 or 1/4 hp, to 060, 075, 090, 110, 150, 180 size that probably handles 1 hp. They are very nicely machined, very smooth, very quiet, backlash free, come in a dozen ratios, and have bearing support on both ends so retrofitting them for belt or direct drive is easy.

New, these are crazy expensive, however, used in nearly new condition Ive picked them up for under $100 for the parallel shaft and under $200 for the angled head.

The odd thing about them is the input and output usually are custom sizes and sellers often have no clue what it has.

Unlike the cheap Chinese planetary drives, or the rather coarse Boston reducers, these are like BMW’s. If the form factor works for your project these are definitely worth looking into.

If you look inside, the parts are made in China.

 

[TaperPin]

If you look inside, the parts are made in China.

Wherever the Germans source their parts from, they run smooth as a sewing machine and the machining makes my Remingtons look bad. The full name is Wittenstein Alpha.

 

[muleystalker]

Looks like cable or wire pulling lube. Would have to smell it.

What's the cable pulling lube smell like?

 

[Larry Koch]

There are many brands, but in the the electric utility business we used a large tube of a white clear runny called polywater https://georgiaunderground.net/products/5-gallon-polywater-prelube-2000.html very similar to this. I been retired for over a decade so things change.

Polywater J Lubricant - 1 Quart Size Squeeze Bottle

Polywater J Lubricant (1 Quart) is a high-performance, water-based gel designed to reduce friction during cable pulls. Ideal for long, multiple-bend installations, it’s clean, slow-drying, and easy to use. Available now at Georgia Underground Superstore!

georgiaunderground.net

 

[nanuk]

To answer your question.... I think part of the reason for that is that the neck opens to release the bullet some amount, the bullet does not slide out of the neck when fired....

if you really think about this, I believe there is NO WAY that happens

I've done some reading on cast bullets and gas cutting, then read up on gas cutting with jacketed

Do you HONESTLY believe the gases go past the bullet BEFORE it starts moving??
have you EVER seen a bullet with carbon on the nose?

To do what you state, the gases would have to move completely past the bullet and out of the case BEFORE any significant bullet movement

and has been shown, primers have the power to move the bullet into the rifling, so the bullet is out of the case and into the rifle BEFORE there is any significant gas pressure to expand the case/necks

It only takes a few LBs pressure to seat a bullet, and it takes even LESS LBs pressure to unseat it.
Although it takes very little pressure to expand brass, I doubt very much the neck has done any expansion before the bullet leaves

Here's something else... carbon on the cartridge case past the neck... IF it works like you say, there'd NEVER be any carbon blown back into the chamber
IF the pressure remained high enough to do so after the brass collapsed back, we'd see carbon on EVERY cartridge fired. But we don't, so we know it probably doesn't

many shooters who have done comparisons have found that as long as the cartridge will chamber without resistance in the neck area of the chamber, it will fire just fine with NO increase in pressures
the ONLY time there will be excess pressure is if something impedes the bullet's forward movement. IE/too tight a neck, noticed when jamming in the cartridge, and too long of brass that jams and crimps into the bullet, same effect as the too tight a chamber neck.


I know we all like to sound like we know what we are talking about, (I sure do. Hahahaaa) but if we just repeat oft quoted ol'd wives' tales, we don't advance the science.

 

[Alex Wheeler]

if you really think about this, I believe there is NO WAY that happens

I've done some reading on cast bullets and gas cutting, then read up on gas cutting with jacketed

Do you HONESTLY believe the gases go past the bullet BEFORE it starts moving??
have you EVER seen a bullet with carbon on the nose?

To do what you state, the gases would have to move completely past the bullet and out of the case BEFORE any significant bullet movement

and has been shown, primers have the power to move the bullet into the rifling, so the bullet is out of the case and into the rifle BEFORE there is any significant gas pressure to expand the case/necks

It only takes a few LBs pressure to seat a bullet, and it takes even LESS LBs pressure to unseat it.
Although it takes very little pressure to expand brass, I doubt very much the neck has done any expansion before the bullet leaves

Here's something else... carbon on the cartridge case past the neck... IF it works like you say, there'd NEVER be any carbon blown back into the chamber
IF the pressure remained high enough to do so after the brass collapsed back, we'd see carbon on EVERY cartridge fired. But we don't, so we know it probably doesn't

many shooters who have done comparisons have found that as long as the cartridge will chamber without resistance in the neck area of the chamber, it will fire just fine with NO increase in pressures
the ONLY time there will be excess pressure is if something impedes the bullet's forward movement. IE/too tight a neck, noticed when jamming in the cartridge, and too long of brass that jams and crimps into the bullet, same effect as the too tight a chamber neck.


I know we all like to sound like we know what we are talking about, (I sure do. Hahahaaa) but if we just repeat oft quoted ol'd wives' tales, we don't advance the science.

Im not repeating anything, just my ideas on what happens based on personal experience. The reason I know the bullet does not just slide out of the neck with no neck expansion is because when that happens the neck will not expand at all because the pressure equalizes on the outside of the neck once the bullet leaves the neck. So the neck has to be expanded before that happens. I have had experience with a rifle with a very long throat and long seated bullet, the bullet was actually sliding out of the neck before pressure could build to expand the necks. So they didnt expand at all.
So far as gas getting in front of the bullet, just watch some high speed video. Theres always a puff of gas in front of the bullet.
So far as carbon on the necks, theres all kinds of variation in brass hardness, spring back, chamber clearance, ext. Theres many reasons why one rifle may get carbon on the case and the other does not. At what point it occurs is anyone's guess. But its a guess.
All of that is my theory on why the actual grip on the bullet shows up on target more that seating friction. It may be why we can make huge changes in the seating friction by altering the surface of the inside of the neck and not see a big difference on target. But changes in the interference fit make big differences on target, but little change on seating force. But thats really what led me to think the neck was expanding in the first place. The fact that I saw interference fit show up on target a lot more than seating force. But thats just a guess as to why, but what I really care about is the target. Please dont start with the science stuff LOL. The scientists are not shooting anywhere near as small as the dumb ole BR shooters that just listen to the target.

 

[L.Sherm]

Maybe a little off topic Alex but I think most of us saw how " follow the science " worked out.

 

[ronemus]

and has been shown, primers have the power to move the bullet into the rifling, so the bullet is out of the case and into the rifle BEFORE there is any significant gas pressure to expand the case/necks

I can tell you from personal experience that is not universally true. I have loaded 2 .223 cases without powder over the years, and neither moved the bullet, and my bullets are moly coated.

 

[Alex Wheeler]

I can tell you from personal experience that is not universally true. I have loaded 2 .223 cases without powder over the years, and neither moved the bullet, and my bullets are moly coated.

I also have had failure to fire in extreme cold. Bullets didnt move. Was also at a match with a guy who forgot powder in a whole row of cases. Tried to fire all 10, none moved. But I have seen them push out as well. Too many variables.

 

[Chaotik]

All of that is my theory on why the actual grip on the bullet shows up on target more that seating friction. It may be why we can make huge changes in the seating friction by altering the surface of the inside of the neck and not see a big difference on target. But changes in the interference fit make big differences on target, but little change on seating force.

I wish there were some way of measuring interference fit.... ?load cell ?strain gauge

 

[Alex Wheeler]

I wish there were some way of measuring interference fit.... ?load cell ?strain gauge

You know, changing bushing until the rifle shoots smallest just works. Measure the before and after neck diameter to get the interference fit, which is what we call neck tension. Even though its not an accurate term we all understand what we are talking about.

 

[D Coots]

"but what I really care about is the target. Please dont start with the science stuff LOL. The scientists are not shooting anywhere near as small as the dumb ole BR shooters that just listen to the target.

B-I-N-G-O

To each their own, but I'm with you....

 

[cveg2887]

Hey Alex. Are you turning into the shoulder on the 6br cases before you fireform?

 

[Alex Wheeler]

Just touching the junction, yes. Not cutting into it.

 

[L.Sherm]

Just touching the junction, yes. Not cutting into it.

Question Alex and others, do you cut out donuts inside the neck at the nk shoulder junction even if your not seating to them?
I do, my thinking is it interrupts the gas flow through the neck and causes turbulence. Right or wrong thinking? or not worth the hassle I havent tested it.

 

[cveg2887]

Just touching the junction, yes. Not cutting into it.

Do you leave them that way or touch-up after fireforming?

 

[Dave M.]

how about 2 inch groups at 1000 yds.

Sounds like someone should go dominate F class nationals….maybe we can get a name to go with that original post, at least so we can track his/her future shooting successes.
Dave

 

[Dave M.]

I don't shoot in matches because I would have to travel 5 to 8 hours to there! look at a map and look where Hays, KS is!!! In between KC and Denver!!! Would love to shoot matches and show yeah what a old marksman can due!!! Even without a scope and F class 6.5x55!!!!

5-8 hours drive??? That’s stopping you from competing??? I drive 4.5 hours each way to compete 7+ times per year.

 

[memilanuk]

5-8 hours drive??? That’s stopping you from competing??? I drive 4.5 hours each way to compete 7+ times per year.

Don't feed the troll. Please. For everyone's sake.

 

[Alex Wheeler]

Do you leave them that way or touch-up after fireforming?

I do not, but some very good shooters do and they do show variation again after being shot some. So if you were really wanting to go all out you could do that.