Mucho Mas Questions, for U Whisper Hooligans

[ray losli]

:confused: .... Have built a few rifles in the past but .30 sub. Vel. platform is a new one to me.
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looking for info on Twist-Rate for 30 ca. whisper on bolt action platform.
I have seen 10 twist mentioned but that seem extremely random for the extreme amount of different Wt. .30 rifle bullets out on the market.
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Want to load on the Heavy max. .30 cal. bullet weight..
Considering / Sierra-220 grn. round nose. / looks like similar bullet shape to what I use accurately in sub-sonic .22 rimfire match rounds.
also:
Any info on Throat Depth on the Chamber Ream would be highly appreciated.
Since it wont be (confined to AR Mag.) Don't want the Large-Weight bullet ridding to far down in the boiler room. Got a little extra OAL to play with a bolt action as a platform.

also:

Is the sub-sonic .30-221 the same as shooting .22 rimfire sub rounds for barrel length. ?
the basic rule of thumb for sub .22 rimfire is that you gain no more velocity over a 16 inch barrel.
Is the same for Vel. on .30-221 sub-rounds . ?
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thanks....... :D
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[Cornholio]

I certainly don't have all the answers to your questions, but I can safely answer two of them.

You are going to want a 1 in 8" twist.

You will get max velocity out of 16" of barrel. The Whisper uses only ~ 6-20 grains of powder, and the slowest powder you will use will be in the magnum pistol-light rifle (i.e. Hodgdon 110-Hodgdon 4198) class. Most people stick to the H110/W296/AA9 powder for all their Whisper needs.

[Quarterbore]

Welcome to the forums... glad we got your account working...

You were given great advise above but to add a little the 1:10 twist is better suited for supersonic loads and lighter bullets. The faster 1:8 twist is needed to stabalize the heavier bullets. Guys shoot the lighter bullets out of the 1:8 twist barrel all the time and it works fine.

As for accurate bullets, I think that just because you have had good luck with a round nose bullet in a 22LR does not mean you will like RN bullets in the Whisper. Try reloading and see what your rifle likes but I am confident you will find other bullets that work better.

As for the chamber and throat area, I really don't know what to suggest here. I assume you are not going to SSK for this work but if you go to a gunsmith that has done a 300/221 Fireball they will simply ream to the specs of the 221 case and be done with it.

If you are looking for a good smith, I like Kurt at Kurts Kustom and he is building me a 300/221 Rem 700 LTR clone at this time and Kurt has made many 300/221s over the years....

Here is a thread on ARFCOM with info on my 300 Whisper project:

http://ar15.com/forums/topic.html?b=2&f=44&t=147625

[ray losli]

This kind info is exactly what I am looking for.
I most likely will have Pac-Nor do the barrel job. They have built a couple barrels for me in the past and they are local/in state.
Not sure if I will go with a Rem. Action. I want to use Sako (pipe dream) / CZ would be another good choice for an action but After-Market choices for a Stock might be the clincher on the deal depending on how big a barrel Diameter I will choose.
I already have a couple of Tactical stock set-ups on 2 Mag. blow-torches / There Big, Heavy, Hot & kick. So I think I will go a smaller and lighter route on this one.
Glass is where the $$$$ is going to get spent on the one though. Hold-over is critical on Lobbing Lead.
I just enjoy Lobbing 40 grn. sub. .22 match rounds so much / I don't see how I would not like a 300-221.
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I don't understand why the accurate (time proven) bullet shape (round nose -flat base) use in .22 sub-sonic match/comp. would not fly accurately in the same way on the larger scale in .30 cal. sub. rounds. / we are not shooting flat, high Vel. / Has someone already proven this wrong ???

Will probably have a few more Q's soon
Big Thanks.........
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[Cornholio]

Quarterbore, how much is the whole rebarrel/thread job costing you?