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Author Topic: .257 cal Monocoque PCP  (Read 54054 times))

Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #200 on: July 03, 2016, 02:13:30 AM »
Yeah, I do have a reamer here, that I made myself a couple of years ago for another gun, but it's pretty crude.... I ordered another one over a year ago and I thought I was never going to get it, but the guy who is making it contacted me just about the time I got the mould for the 100 gr. bullets, and I figured I would wait for him to supply it.... That didn't happen before the Motel got busy, and I still haven't got it.... So now I won't have time to do much anyway until the fall, so I may as well wait for the new reamer.... If I don't have it by the time I can work on the gun, I will be forced to use the one I already have.... Make sense now?....  ::)

I appreciate your eagerness, rest assured I'm not dragging my heels because I want to.... I just want to do the best job possible, I think you can understand that?....

Bob
« Last Edit: July 03, 2016, 02:20:55 AM by rsterne »
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).

Offline rifle50

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Re: .257 cal Monocoque PCP
« Reply #201 on: July 03, 2016, 02:19:15 AM »
Yeah, I do have a reamer here, that I made myself a couple of years ago for another gun, but it's pretty crude.... I ordered another one over a year ago and I thought I was never going to get it, but the guy who is making it contacted me just about the time I got the mould for the 100 gr. bullets, and I figured I would wait for him to supply it.... That didn't happen before the Motel got busy, and I still haven't got it.... So now I won't have time to do much anyway until the fall, so I may as well wait for the new reamer.... If I don't have it by the time I can work on the gun, I will be forced to use the one I already have.... Make sense now?....  ::)

I appreciate your eagerness, rest assured I'm not dragging my heels because I want to.... I just want to do the best job possible, I think you can understand that?....

Bob

Thanks for the enlightenment.......Definitely understand doing the best possible.............Carl
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Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #202 on: July 03, 2016, 02:21:02 AM »
In addition, there is a possibility that NOE may eventually figure out how to make the tooling to do the 112 gr. bullets, and I would really like to cut a chamber to fit both.... I'm hoping that will all come together this fall....

Bob
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).

Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #203 on: December 11, 2016, 02:00:14 PM »
Just a note here, to bring everyone up to date.... I couple of months ago I received a mould for the 112 gr. BBT.... I have still not received the chamber reamer I ordered from Sean Pero, and I can't contact him, so I may well have to either use the crude reamer I have, or make another one.... While waiting for winter to roll around and have some shop time, I ordered two more moulds from NOE (one each, 101 gr. and 112 gr.) and had them sent to Erik at Hollowpoint Mould Services for conversion to HP.... This will involve pushing the nose back on both bullet to a 50% Meplat for the 1/8" HP pins, and the weights for the HP versions will be about 97 gr. and 107 gr., possibly a bit less depending on the cavity size that Erik can achieve.... My wife ordered these for me for Christmas, bless her heart.... At the moment I only have a 0.257" sizing die, but will be ordering bushings from NOE to fit their sizer a couple of thou either side of that.... so that I can play with bullet diameter as well....

The plan is to get this rifle to the point of firing it this winter, so that I can at least see if it works, and assess the FPE limits at various pressures.... I still have to make another inline regulator set for 3600-3800 psi for tethering, depending on the pressure required to drive the bullets at suitable velocities.... Early in the spring I will be building a new "semi-portable" shooting bench that I can transport in my new Defender SxS.... so I hopefully will have a shooting setup worthy of the gun.... I still have my fingers crossed that I may be able to take my first Varmints with it in 2017.... Wish me luck !!!

Bob
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).

Offline William

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Re: .257 cal Monocoque PCP
« Reply #204 on: December 11, 2016, 02:33:28 PM »
Thats some good news, even though it has been delayed a little!  Just praying your reamer or one you may have to make works well.  Sounds like to me that you may very well be shooting some varmints early this spring or when the weather permits!

Sure wish you had that reamer :-[
Don't worry your plans will come together, you seem to have a way with making things happen  :D

Anyway Bob,

To you as well as your family and friends,

Merry Christmas to you all, God Bless

William & Family
  • Mississippi
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Offline Tofazfou

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Re: .257 cal Monocoque PCP
« Reply #205 on: December 11, 2016, 03:18:27 PM »
Bob,

Can't you get custom reamers from McMaster Carr?  I think Doug gets his reamers from there to do my airguns.  He just ordered a special size and i think McMaster is where it came from.  And it got there in less that 2 days.  Could be wrong about McMaster.  Just not worthy to be waiting this long for a reamer
« Last Edit: December 11, 2016, 03:23:10 PM by Tofazfou »
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Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #206 on: December 11, 2016, 04:41:21 PM »
McMaster Carr won't ship to Canada.... I would seriously doubt they make chamber reamers, with a pilot, tapered leade, and chamber all in one.... but I could be mistaken.... never thought to ask.... It didn't really matter once the reamer wasn't here by May, I was dead in the water for shop time until November anyway....

Bob
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).

Offline dyotat100

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Re: .257 cal Monocoque PCP
« Reply #207 on: December 11, 2016, 05:24:08 PM »
They don't have tapered reamers. I use straight reamer and then use a tapered stone file to make the taper. I always ream it smaller and use 400 to make it perfect.

Can't have a real tapered reamer for every caliber.

I do have 2 257, 2 308 and a 338 with 1 degree taper.  257 is .25680" and then I use 400 to polish the straight to hand fit a sized slug for the condors.


Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #208 on: December 11, 2016, 05:32:35 PM »
The reamer I was waiting for is like the one I have for my 7mm....



I have made similar ones myself, but only with a single cutting edge.... They work OK, but I prefer Sean's (above)....



Both reamers cut the tapered leade and the parallel chamber in one operation.... You vary the depth to suit the longest bullet you want to use, just as you would doing it by hand....

Bob
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).

Offline dyotat100

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Re: .257 cal Monocoque PCP
« Reply #209 on: December 11, 2016, 05:46:08 PM »
Yes I have 6 flute carbide chamber reamers. They have a 1 degree taper on them and have a pin on the front for a guide  bushing.

Tom found this guy and he makes them exactly the size you ask for. I always have them made .0002" under bore size so I can make sure I get a nice fit for the condors. Not having a bolt I make them so they push in and won't fall back if you point the gun straight up.

I have to get one made for the 7mm. It was a expensive barrel and worth having a $130 reamer made.

Offline Tofazfou

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Re: .257 cal Monocoque PCP
« Reply #210 on: December 11, 2016, 07:26:18 PM »
Cool Bob.  I see.

Just wanting to help.  After reading your updates, I thought about Doug and his reamers and figured i would try and pass along the info if it helped.

Eagerly awaiting your build results.....

Tofazfou
  • California

Offline Michael Loar

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Re: .257 cal Monocoque PCP
« Reply #211 on: December 11, 2016, 09:21:00 PM »
Bob
Thanks for the update on the monocoque as I knew the last time I asked you said you were still waiting on the moulds I thought but I see know you got those and are waiting on the reamer to finish the project. Hopefully you will get some word on the reamers or find another source so you don't have to use your homemade one if possible.

Thanks for responding to my inquiry and keep us up to date on this cool project.

Mike
  • Oxford, Alabama
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Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #212 on: December 15, 2016, 07:43:32 PM »
I finally got around to casting some of the 113 gr. bullets today....



By comparision, here are the 100 gr. which I did a while back....



The 113 gr. is pretty much a scaled down .308 Whiteout (which was 200 gr.).... The chamber will be cut to accommodate both....

Bob
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).

Offline Tofazfou

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Re: .257 cal Monocoque PCP
« Reply #213 on: December 15, 2016, 09:58:58 PM »
Oh man, my trigger finger is seriously itching.  For scientific purposes ;), i would love to try a handful of those to see if they would work in my TD.  Just for shucks and giggles of course.  I'm curious about them as i love the design.
  • California

Offline lloyd-ss

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Re: .257 cal Monocoque PCP
« Reply #214 on: December 16, 2016, 01:04:46 AM »
Bob,
I've got a nice reamer like in the top pic in reply #208  .2475/.2590.  I am pretty sure it was made by Sean. Looks like his work.
Also have the same type of reamer for the .30 cal TJ's barrels, .293/.301.
Lloyd
  • Central Virginia
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My YouTube channel is    Airgun Lab

Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #215 on: December 16, 2016, 01:27:46 AM »
Lloyd, I may end up borrowing that .257 cal.... I also have one of Sean's in .30 cal just like yours....

Bob
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).

Offline dyotat100

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Re: .257 cal Monocoque PCP
« Reply #216 on: December 16, 2016, 01:44:53 AM »
What does your barrel slug?

.259" is .002" larger then the bullets I shoot in my TJ barrel.


Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #217 on: December 16, 2016, 02:19:01 AM »
I would have to check it again.... IIRC it's 0.248" land and 0.257" groove, with a 7" twist.... How big do you make your chambers, Doug, relative to the groove diameter?.... I find that even if you try to make the reamer dead on, it always cuts a couple of thou larger....

Bob
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).

Offline dyotat100

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Re: .257 cal Monocoque PCP
« Reply #218 on: December 16, 2016, 02:39:36 AM »
I make it so the bullet I'm shooting fits snug. I have 2 reamers. One is .25660" and the other is .25680". They cut pretty much what they are. I also use a floating reamer holder from PTG.

Then I take 400 grit paper on a rod and polish it till I get the perfect fit.

I used a piece of peek push on the pin and then machine it to size on the reamer.

The floating reamer let's the ream line up perfect with the bore.

Here are 2 257, a 308 and 338

Offline rsterne

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Re: .257 cal Monocoque PCP
« Reply #219 on: December 16, 2016, 12:26:10 PM »
Nice!.... I have a LOT to learn about barrel prep, thanks !!!

Bob
  • Coalmont, BC, Canada
🇺🇦 Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since! 🇺🇦

Airsenal:
1750 CO2 Carbine, .177 Uber-Pumper, .22 Uber-Carbine, .25 Discovery, 2260 PCP 8-shot Carbine, 2260 HPA (37 FPE), 2560 HPA (52 FPE), XS-60c HPA in .30 cal (90 FPE), .22 cal QB79 HPA, Disco Doubles in .22, .25 & .30 cal, "Hayabusa" Custom PCP Project (Mk.I is .22 & .25 cal regulated; Mk.II is .224, .257, 7mm, .308 & .357; Mk.III is .410 shotgun and .458 cal), .257 "Monocoque" Benchrest PCP, .172/6mm Regulated PCP and .224/.257 Unregulated, Three regulated BRods in .25 cal (70 FPE), .30 cal (100 FPE) & .35 cal (145 FPE), .257 Condor (180 FPE).