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File 14034067509.jpg - (898.38KB , 1920x979 , box1.jpg )
2774 No. 2774 ID: 0066b5
Here I thought a name like "strip club" would attract attention.

Well we're kicking this strip up a notch, because we're starting with a box.

So what could be inside?
112 posts omitted. Last 50 shown. Expand all images
>> No. 2962 ID: 0066b5
>>2961
I'll be cleaning it with Wipeout before casting. Hopefully that will work.

If not, I'll try it anyway. CerroSafe casts at temperatures a little lower than boiling water, and the chamber is pretty clean. I won't be casting that far down the barrel, just chamber, freebore, and maybe an inch of rifling. If it does contaminate, it shouldn't contaminate too much.

Apparently, Cerrosafe is more sensitive to over-heating than much else. Not sure how much it would alloy from such low temperature...
>> No. 2963 ID: 7188a3
>>2953
>>2956
Thanks for clearing that up. I was all kinds of confused there.

Also, if cerrosafe doesn't work for whatever reason, I've heard of people using sulfur to make a cast. I guess at low enough temperatures it won't react with the steel, but it'd still make me nervous.
>> No. 2964 ID: 67f943
>>2962
I'm not sure what your background in metallurgy is, so I apologize ahead of time if I sound condescending.

Some metals can alloy at room temperature, a prime example of this is mercury, forming amalgams with many other (solid) metals.
Cerrosafe is just a commercial name for Wood's Metal, and while I'm not sure if it will alloy with the metals present in the barrel, I am cautious about liquid metals being in contact with other metals, liquid or not.

On more factual grounds, Wood's metal is wonderfully toxic (cadmium and lead!), so wear gloves and all that.
>> No. 2966 ID: 0066b5
>>2964
Cerrosafe isn't exactly Wood's
http://www.lowdenlimited.co.uk/LowMelting/SafeAlloy.html

But it must be quite close to it. It's true that I don't know much about metallurgy, I just cut the stuff, I don't melt it.
>> No. 2970 ID: 68221d
File 140652114659.jpg - (2.25MB , 3468x1058 , suou2.jpg )
2970
Now with 100% more legs!

this picture was one of the most niggering things I've had to do in a long time of being shit a photography
Rifle too long to photograph regularly without moving whole apartment around. Put camera up higher. Camera butts up against the ceiling. Can't see how the camera is framing because I can't fit my head between ceiling and camera. Use mirror. Camera goes to sleep. Wake up camera. No room between ceiling and camera to bounce flash. Set camera on 2 second exposure, grab flash in my hands. Turn off all lights so they won't contaminate bounce flash during 2 second exposure. Need to let camera focus, grab flashlight. Use phone to remote fire camera. Need three hands to shine flashlight on spot I want the camera to focus, trigger camera with phone, chuck all that shit aside, grab flash and fire it off at ceiling before exposure is over.

Picture still looks like ass. I need a drink.

>> No. 2994 ID: f48366
So the fabled Wipeout does nothing.

I'm noticing a small reduction in the bore fouling when I brush. This residue must be somehow immune to chemicals, but seems to slowly brush off. I've started simply squirting oil down the barrel and brushing with vigor.

It appears to be getting an estimated 10% reduction per 100 strokes. I prepare my fap hand for this one.
>> No. 2995 ID: 7188a3
>>2994
I wouldn't generally recommend this, but you might do better with a fine lapping compound like J-B as long as you go very very carefully. Is it coming out as flakes or what?

If I were you, I'd actually keep it as is until you put some rounds through it and test for precision. If you aren't satisfied, you could then fire lap it to see if it improves. I'd just be worried about removing something that turns out is supposed to be there.
>> No. 2996 ID: 7a7c7b
>>2995
No flakes. I'll see how this goes today, and keep rubbing until my arm falls off.

The residue can actually be seen here >>2823 and here >>2824.

I'm not going to fire-lap or use an abrasive, unless I actually lead cast lap the bore. The previous two just aren't right.
>> No. 2997 ID: 7188a3
>>2996
At least it seems to be just sitting in the low spots.

If you have a whole lot of mercury lying around you could try flood the bore with it. Pure copper only amalgamates with great difficulty, but lead, zinc, tin, and other low-temp-melting relatively-nonreactive metals will dissolve just fine without producing a galvanic cell that attacks the steel. Loosened bits of fouling float to the top and you just filter the mercury through a bit of old t-shirt into an airtight container to reuse. If mercury can severely weaken and embrittle old once-fired fulminate-primed brass cases, it might help with your problem.

Of course, there aren't too many people with loads of quicksilver just lying around anymore. It's not as dangerous as the environmentalists make it out to be IF you have adequate ventilation and can prevent droplets from spills going all the fuck over the place. Zinc sponge and flowers of sulfur are useful in the latter case.
>> No. 2998 ID: 7a7c7b
>>2997
I think I'll just leave it.

Good news though, I found some brass. I might not even have to cast the chamber, when I fire the first round, I'll be able to measure the brass case itself.

I have primers and powder, so the big thing now is slugging and making bullets. Not exactly difficult, but I have to find the right copper to make bullets from.
>> No. 2999 ID: 4416e5
Update:

20 brass cases to pick up from the post office (thanks Sebarms)
Bore slugged (.5881)
Primers obtained
Powder obtained
>> No. 3000 ID: c97812
>>2999
>Bore slugged (.5881)

That's within expected parameters. Neat. I wonder how she'll shoot.
>> No. 3001 ID: 4416e5
File 140907912413.jpg - (148.91KB , 1279x681 , P82s65099.jpg )
3001
>>3000
Well the exact size isn't crucial compared to the state of the rifling, because I can compensate for that stuff when making my own bullets. I am quite hopeful for good accuracy, because the rifling is pretty nice, and should shoot the properly fitted bullets rather well.

Got my cases in. I chucked about 10 in the tumbler before going "yeah it ain't gonna fit more than that". Tumbler is a Lyman Turbo Pro 1200, and should be able to take 125 cases of 30-06, lol.

I got three steel bullets that I probably won't fire, but I'll be able to use them as a reference when I make my own.
>> No. 3002 ID: 7188a3
>>3000
>>3000
>>3000
>>3000
>>3000
>>3000
>mod get out >:(

Jokes aside, It's terrific you got components lined up, WarPlanRed. JBM ballistics has an excellent bullet stabilization calculator that will give you an idea what sort of projectiles will stabilize in your rifle and how much drag they'll experience in flight. http://www.jbmballistics.com/cgi-bin/jbmdrag-5.1.cgi
What sort of primers does that thing use, anyways?
>> No. 3003 ID: b10277
>>3002
I fiddled around about a month ago with bullet designs, going off G7 profiles, then using that to come up with volumes and then weight in copper, to find out how long I could go before twist started being an issue, as copper isn't that dense.

I might have to press in a lead core, if my math isn't totally off. The PTRD seems to have a relatively slow twist, as far as Russian military guns go; I'm used to nuggets and stuff with twists quick enough for 240 grains...

For primers, I have to cut the primers pocket open, press fit a bushing for 50BMG primers (CCI#35).

I think they didn't intend to use long bullets in the PTRD. It'll be something to try out.
>> No. 3004 ID: 9ebbb1
>>3001
>Well the exact size isn't crucial compared to the state of the rifling, because I can compensate for that stuff when making my own bullets.

Sure, but the wider the slug came out, the more likely there would be (uneven) wear on the rifling too.
>> No. 3005 ID: 8a8453
>>3004
Pushing the slug through, you get the feeling for the barrel if it has rough spots or tight spots. All things considered, this one wasn't too bad.

Would have been a lot better without the Immortal Fouling of Chemical and Physical Immunity.
>> No. 3013 ID: 1d86b1
File 140942185360.jpg - (464.95KB , 3329x605 , 5234423.jpg )
3013
I'm a little surprised at how well this worked out, the shipping box was really cumbersome.
>> No. 3194 ID: 327c77
File 141833567470.png - (932.15KB , 926x960 , 2014-12-11 17_05_06.png )
3194
Finally got around to priming things. I'll do as many as I can tonight.
>> No. 3195 ID: a5dca8
>>3194
Looks good. Stainless bushing?
>> No. 3196 ID: 6ab689
File 141843960525.jpg - (1.04MB , 2477x1394 , 20141211_191114.jpg )
3196
>>3195
I had a rod of 3/8ths 1045 (regular cheap shit) that was wonderful for this.

The CCI #35 .50BMG primer is .225" thick with a diameter of .317", while the Russian Berdan is .200" thick and has a diameter of .355". I merely had to drill the rod with a 19/64ths drill and bore it to .316".

Had to make my own babby boring bar with a bit of HSS.
>> No. 3197 ID: 6ab689
File 141843975080.jpg - (614.50KB , 1860x1136 , 20141211_191812.jpg )
3197
I used the lathe dog to push the primer in the bushing, and then parted the bushing off the rest of the rod with a cutoff tool.

The front of a drill chuck is pretty flat, and the square rod was to ensure the primer wasn't pushed in at an angle.
>> No. 3198 ID: 6ab689
File 141843983645.jpg - (689.33KB , 1793x1287 , 20141211_194436.jpg )
3198
The case primer pockets were just bored 0.025" deeper, and .374" in pocket diameter.

Finished the week with 15 primed cases, ready for powder and bullet.
>> No. 3199 ID: 6ab689
File 141843993090.jpg - (768.73KB , 2212x1131 , 20141211_185919.jpg )
3199
Reloading presses are for quitters.
>> No. 3200 ID: 6ab689
As for the projectile, I found a few options.

First, I could buy CNC turned solid copper or brass bullets. The problem with those is the price. They end up being $20 dollars per projectile. Twenty fucking dollars.

Second, I could get a copper rod, that would cost me $75 for 3 feet, and machine my own bullets by hand. That's not so bad, I can match them for the bore diameter and everything.

Third, I could get nylon or teflon rod and make sabots for either stock 50 BMG bullets, or straight up 1045 bar stock. Or an old bit of HSS from an endmill shank. Or even carbide.

Fourth, I can swage copper tubing onto a steel rod, and turn them both on the lathe simultaneously to bullet shape, with only the cannelured copper as bearing surface. I'm looking around for the proper copper tubing right now.

I'll ask at work for the nylon or whatever plastic I could use as a sabot, because that might very well be the cheapest option while requiring the least amount of work.

Final note:
Right now I'm trying to focus on making this as safe as possible, such is the priority. Second is trying to keep it relatively low cost, because I want to put more than ten rounds per year through it without having to sell my kidneys. Third, is some measure of accuracy (car engine block at 50 yards). Fourth is seeing how long the components can last if I keep MV at 3100ft/s or so.
>> No. 3201 ID: dc0192
File 141849780718.jpg - (69.44KB , 800x532 , gas checks.jpg )
3201
>>3200

This might be a stupid question since I don't know anything about guns this size, but why is hardcast lead with gas check omitted as an option? Is there an integrity issue?

That much lead would obviously have to be bought in bulk & not from the usual recycling sources, and making the custom mold would be somewhat an investment, but in the long run it's probably something you'll be able to shoot more often than the other options?
>> No. 3202 ID: 006111
>>3201
Ah yes. I have no trouble with that sort of projectile, and will be machining my own mold. However, there's a limit to how hard you can drive even well lubed, sized, gas checked lead without getting intense fouling, so I'd be doing it with the reduced capacity stainless cases. Those cases are to be machined to the same external dimensions of regular cases, but bored to a straight internal diameter, usually called an "everlast" design. This reduced internal capacity would limit powder load so that a reasonable muzzle velocity with mellow operating pressure can be achieved without difficulty.

Tl;dr with regular full cases I don't want to have to scrub lead out of that fucking bajillion feet long bore. I hear Trail Boss can be used in a full case, I'll have to try that too.

I also want that gun for what it was meant to shoot, i.e. an angry steel core 1000 grain bullet at 3000ft/s+ (the factory specs for the early WW2 stuff was actually 3200 to 3300 with a 990 to 1000 grain bullet, but I'd rather be a little more on the safe side when a beer bottle sized round is going off a few inches from my face). I spoke to another guy up here with a PTRD and he said lead loads were nice and all, but let's be honest, we didn't get that gun to load it like grandpa's .577 Snider.
>> No. 3203 ID: dc0192
>>3202

Alright, makes sense.

With a gun like that, I'd surely make some loads like you described. Sounds like good fun. And the loads being reduced or not... You're still shooting like 900 grain of lead. That shit is going to pack a whallop. Whatever it'll hit, it'll be pretty spectacular.
>> No. 3204 ID: 006111
>>3203
I'll probably skip right over 900 grain lead and go straight to more weight to make up for slower velocity. Whatever the twist can stabilize, also fuck streamline shapes, they increase bullet length for similar mass.

If I make a lead bullet, it'll be a flying brick. Except less aerodynamic and heavier. Because fuck everything. Just a big flat based round nosed hamburger (quarter pounder) or even cheeseburger if the twist can swing it.
>> No. 3206 ID: 7188a3
File 141853956611.jpg - (331.15KB , 2400x1600 , 37mm_projo1.jpg )
3206
>>3200
I am very much a fan of the plastic sabots idea. Of course, if you were to figure out a way to make groove-diameter plastic jackets around a bore riding steel core, I'd be a much bigger fan of that.

In fact, have you considered using driving bands? They could be made with copper or plastic.
>> No. 3207 ID: d35b85
>>3206
See
>>3200
>> No. 3208 ID: 6ab689
File 141870063934.jpg - (2.01MB , 4128x2322 , 20141215_204907[1].jpg )
3208
>bored
>grab CCI #35
>put on plate on burner
>put on hearing protection
>put on eye protection
>couple minutes pass
>POW
>honeydew sized, bright, flash fireball
>noggin begins to churn
>machine out primer pocket of .38 SPL case
>press in #35 primer
>seat lead bullet

Sadly, a Ruger GP100's hammer doesn't have the juice to do much more than scratch the primer. Was kinda cool to think about though, I bet the bullet would have left the barrel.
>> No. 3209 ID: dc0192
File 141875491356.gif - (505.94KB , 499x374 , 53a5509d06d7c11f.gif )
3209
>>3208

Found WarPlanRed.
>> No. 3210 ID: 6ab689
File 141878446779.gif - (1.83MB , 275x154 , 1388804771207.gif )
3210
>>3209
That hurts man.

I really don't like monkeys
>> No. 3218 ID: 6f5839
>PTRD41
Neat. I see also that you've been able to obtain 14.5mm ammunition.

I hate to ask, but is there any way to mount an optical sight? A rifle in 14.5mm seems to cry out for one, for the same reason that modern .50 BMG target rifles as a general rule have an optic of some kind as the primary sighting mechanism.

Also, let us know what kind of groups you get with it the next time you go and horse around hurr hurr hurr at the range. Wikipedia quotes translated Russian training documents suggesting the original accuracy standards were around 1.2 mrad/5 MOA with delinked MG ammo. This is not unreasonable, given the expected target size and the quality of ammunition manufactured for a belt-fed, area-fire weapon. But I should think the weapon itself would be capable of better, with better quality ammunition. We need to start a write-in campaign and bother Sierra Bullets until they release a 1000gr .58 caliber MatchKing.
>> No. 3219 ID: 6ab689
>>3218
>obtain
More like painstakingly assemble from scratch and still don't have actual load data for. Also the projos are still in development.

I might make a sight mount that requires no modification of the rifle at all (make a mount that clamps against the barrel). It would be aluminum so it wouldn't scratch the rifle. I'm kinda hoping for 3 arcmin, give or take (hopefully take) 1 arcmin.
>> No. 3412 ID: c3e6b2
  Here is a PTRS in action
>> No. 3413 ID: e8a108
>>3412
I'm all kinds of jelly.
>> No. 3414 ID: 70d38f
  >>2970
>>3412
And here's PTRD.
>> No. 3415 ID: 0066b5
>>3414
I would do unholy things to see a little russian girl with short red hair do that.
>> No. 3481 ID: e8af03
>>2774
How goes the work on this project? I just read this whole thread and am excited to see how your bullets are coming or if the barrel ever got clean.
>> No. 3482 ID: 2f62b7
>>3481
Don't think the barrel will ever be clean, to be honest.

For bullets and the rest, still on hold due to reasons. I need to make a few calls and set up a meeting at work to see if I can subcontract bullets or something, but it'll be a little while.

I'll post updates as they happen.
>> No. 3485 ID: 26cfa0
Having read this thread longt time ago, I dont remember if you tried electrolytic removal of the shit inside your barrel, but Ill toss you a link to some guy on Reddit describing the way its done quite good.

https://www.reddit.com/r/gunnitxt/comments/xccpu/a_step_by_step_guide_to_electrolytic_cleaning_of/

We used to do this exact thing with our M107 and Browning HMG barrels when I was still with the army, mind you we used a power-supply so we could get the best results, but the trick with the phonecharger works to.
>> No. 3535 ID: 6372b6
Okay so projos are in the works. Stock material should be on order by next week.
>> No. 3544 ID: 6057a8
File 144442856218.jpg - (75.96KB , 550x367 , soon-9.jpg )
3544
Material has arrived, just waiting on a lathe to free up.
>> No. 3545 ID: f9905a
>>3544
So after talking to you on the other Chan I tried the e-mail.
It was for the other PTRD owner in niagra. Let him know about the possibilty of bullets since he missed the thread.
Probably going to order the dies sometime soon.
Shoot me an e-mail at thefrogge at hotmail.
>> No. 3546 ID: 6372b6
>>3545
Sent
>> No. 3576 ID: 7da887
File 145134598793.jpg - (171.83KB , 728x917 , 1206746885873.jpg )
3576
>>2774
Found pictures!
>> No. 3577 ID: 7da887
File 14513460004.jpg - (189.90KB , 716x946 , 1206746919924.jpg )
3577
>> No. 3578 ID: 7da887
File 145134600781.jpg - (155.49KB , 704x946 , 1206746952304.jpg )
3578
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