20 Vartarg reamer specs , design

[CajunBlake]

fixing to buy a 20VT reamer as Dave Kiff (PTG) has one with a standard .232" neck and .0503" freebore. The print is dated 2010 and pretty sure this was Todd Kindler's original design from years ago.

I have no problem with the neck, since I will be using Lapua brass exclusively and neck turning to fit the chamber.

just curious if the aforementioned FB will be suitable with 32-39 gr pills to kiss the lands ? What FB is your current 20VT chamber(s) ?

I'm probably over-analyzing things worrying about nothing since this cartridge has been proven in the fields and from the bench. I'm sure PTG has sold dozens of 20VT reamers based on these same dimensions with zero complaints.

Should I just buy the reamer , chamber my Lilja barrel and be done with it or design a new reamer with different FB specs and wait 6-8 weeks for the delivery ?

noted info: Stiller TAC30 single shot action and the 32 gr Sierra and 35gr Berger will be my primary bullets of choice. 39 gr Sierras if I want to shoot the heavies

what would you guys do , thanks

 

[Rick in Oregon]

Cajun, I'm looking at Todd's 20VT chamber drawing in his "20's" book, and you are correct in that the listed freebore is .050", and is dated 12-96, the year he designed the 20VT.

Can't say much about weather or not to design a reamer with tighter spec's or not, as my Cooper factory barrel shoots any of the 32's better than I can, as it's proven it's capable of shooting in the .1's. How often I can do that is not the rifle's problem.

You'd probably be good to go with Dave's reamer spec's he has on hand for this neat little caliber.

 

[tclaunch]

tonyb sent me a print of his reamer drawing, and it is the very one of which you speak. I`d ask him this, but he told me thru PM he shoots a lot of 32 Blitzkings. I just ordered a reamer from PT&G with .233" ND and .030" FB. I was wanting a reamer that you "can" shoot no turn, but tight enough to shoot a turned neck and be 100% clean. I believe I got it right.

I plan to shoot 32 Sierras, and Lapua brass exclusively.

 

[JohnHenry]

The first link is a link to the PTG 20 Vartarg reamer sold by grizzly.com and indicates a .232 neck diameter and .0503 freebore. It also indicates a .374 diameter measured at .200 above the base. The second link is the saami maximum cartridge(upper print) and minimum chamber(lower print) specs for the 221 Fireball.I would have some concern that the 20 Vartarg reamer diameter(.374) measured at .200 above the base is less than the 221 Fireball minimum chamber spec(.3769). Admittedly speculation, but Kindler may have reduced the diameter at this point based on the diameter of 221 Remington brass. The diameter of Lapua 221 Fireball brass is greater than Remington brass measured at .200 above the base. My lot of Lapua brass measures .3754 at this point and my lot of Remington brass measures .3729. I believe I would specify a 20 Vartarg reamer having a diameter at .200 above the base equal to the minimum 221 Fireball chamber spec(.3769) if I was planning on using Lapua brass.

http://cdn0.grizzly.com/specsheets/t23225_as.pdf

http://saami.org/PubResources/CC_Drawings/Rifle/221%20Remington%20Fireball.pdf

 

[CajunBlake]

thx for the insight JH and others who replied & sent PM's

Has anyone designed a new reamer within the last 6-9 months solely based on Lapua 221 FB brass dimensions ?

I may decide to go this route (new reamer) after speaking with Dave Kiff next week and doing more research after others reply to this thread.

I have 500 pcs of Lapua brass which I strictly plan to use for my 20VT

 

[JohnHenry]

CajunBlake, May be beneficial to send Dave Kiff a sample of your 221 Lapua brass. I know at one time, Todd Kindler was an advocate of that approach.

 

[Rocksniper]

Looks like there's gonna be a few 20vt builds in the works.

I spoke to Dave at PTG last month and this is what he recommended for my build.
20vt for Lapua brass and 32gr SBK.
.2335 NK no turn Lapua
.010 freebore
.3752 base at .200
.060 radius at neck shoulder junction

Hope it all works out.

 

[CajunBlake]

thx Rock

guess I'll be calling Dave on Monday

 

[NorCalMikie]

I ordered up a 20 VT reamer with a .234 neck (PT&G) so I didn't have to turn necks. Also with zero freebore. Works like a champ. Cut two chambers with it and sold it.
Depends on which brass you use. New Remington .221 Fireball brass seemed to be pretty good. Case neck measurement (loaded) was just at .230. Fired and formed Fireball brass was all over the place so the .234 neck worked great.

 

[tclaunch]

Looks like there's gonna be a few 20vt builds in the works.

I spoke to Dave at PTG last month and this is what he recommended for my build.
20vt for Lapua brass and 32gr SBK.
.2335 NK no turn Lapua
.010 freebore
.3752 base at .200
.060 radius at neck shoulder junction

Hope it all works out.

I really like these numbers! I toyed with the .2335" and settled on .233" I was in the dark on base @ .200" as I have not ordered my S-Type FL die. I think I like my FB better, Dave wants bearing surface exactly at the neck/shoulder, I like the bullet just ahead. Thanks for posting, I`ll call in a change on Monday and pay the new fee..... :-[

 

[SS427]

Does anyone know the specs of the reamer Cooper uses for the .20 VT? From what I can tell with the 32 grain and 35 grain bullets I use, it has the perfect free bore and other dimensions. Pretty sure it is a .232 neck.

I want to order the same spec reamer for a custom build I'm saving up for.

I know...call Cooper and ask. I doubt they will tell me, but if you think they will, I will call them.

 

[CajunBlake]

years ago before the buyout, I use to call Rob Behr at Cooper and talk guns and cartridges . Since he's no longer there, I have no contacts at Cooper

if someone over on Saubier does know the specs, you could do a chamber cast with cerrosafe and confirm the specs

 

[Rick in Oregon]

Otter, I sent my Cooper 204R to the factory to have the barrel cut and crowned to 24", and while it was there, I had them make a chamber cast and send it to me. I was under the impression that all their .20 cal necks were .232" too, but it's a solid .234".

Also, Hornady sent me their engineering drawing for the 204R when it first came out, and it lists a neck of .234" also. Have not verified the neck I.D. of my Cooper 20VT yet, but it makes me wonder too. I'll be interested to hear what Cooper tells you.

 

[Dvldawg]

Don't recall the NK diameter of my 20VT finish reamer, but I do know that I went with 0 FB, with the intentions of shooting 32 gr bullets.