.338 Spectre

dthunter

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Hi you gunnutz!
A friend of mine wants to build a .338 spector with a tight twist(6.5") I believe.
He wants to build it for a T/C Encore frame,maybe modify or rebore an exsisting barrel out from .22 to .338. Some kind of bolt rifle he would be happy with as a secondary rifle option.

I am not very familiar with this kind of project, so come on you gunnutz and give me some much needed info/ Ideas/Options

Have fun, and straight shot'in!
 
I know very little about that chambering, but I would discourage that idea for the following reason......The best platform for a very accurate rifle is a bolt action of one form or another not the Encore.....A good friend has rung out countless after market and factory barrels on the Encore and comes to the conclusion that most single shots of the drop block variety(Ruger, Browning, Hi-wall, etc) produce better results then the TC. The bolt action is still the most capable with modern high pressure ammo.
He abandoned the project and like me, when it doesn't work out, get rid of it and get on with the next....I'd spend hard earned money on the project that has the best accuracy potential....a solid bolt action!!!
 
I couldnt aggree more Ben!
I would stick with a bolt accross the board as well if I want accuracy to be a priority.
The big problem is there is no bolt faces that are the same diameter as the Spectre. (the same as the 6.8SPC). I am hoping someone is aware of an option I am missing.
I thought of boreing out the face of a .223 bolt face and get the barrel custom made(1-6.5"twist).
Does anyone know of a super quiet subsonic round with a .308 size bolt face, or .223bolt face?
 
Why would he choose .338 Spectre over .338 Whisper (.338 BR)?

The parent case for the Spectre is an oddball: 10mm magnum, the only one who makes them is Starline. You can form them from 6.8 SPC, but that involves trimming.

You get the same ballistics with .338 Whisper and all that is required is necking up 6mm BR or 7mm BR brass, which will be of much higher quality to begin with and it uses the same bolt face as .308 Win. There is also .338 Quiet which is basically the same, but with slight changes to the reamer to avoid royalty fees.

midgets.jpg
 
How many grains of what powder and how heavy a bullet? What's the velocity and drop from 100yds to 300yds or is it really ment for distances that far?
 
Not my rounds, but he's loading around 11.3 gr. of Bluedot with a 300 gr. SMK or Scenar at around 1080 fps. out of a 16.5" barrel, I believe.

It'll work at 300 yards...
 
I toyed around with the idea of a .338 Whisper/Quiet before I built my .300 AAC Blackout but I could find next to nothing in the way of information on the round. It was going to be a cast lead only endeavour for me. The thought of spending big bucks on match grade .338 cal. bullets for what essentially was going to be a 200 yard rifle wasn't really appealing to me.
 
Thats the kind of thing I'm looking for Kombayotch! Right on!
Give me more info/ links etc.
I am trying to discourage my friend from going with the Spectre because there is just too much crap to modify!

Do you shoot the .338 Whisper?
What action etc?
 
Thats the kind of thing I'm looking for Kombayotch! Right on!
Give me more info/ links etc.
I am trying to discourage my friend from going with the Spectre because there is just too much crap to modify!

Do you shoot the .338 Whisper?
What action etc?

If your friend wants to do the project with minimal investment, tell him to pick up a 700 SPS and uses the donor action and magazine/floor plate assembly with it. He'll get acceptable results and not a lot of money spent.
 
2bad4u:
I made that suggestion to my friend, but I am trying to keep it simple,and inexpensive.

I have a totally unrelated question for u. Whats up with the "i love u max owner" thing on your profile? Just curious.
 
I didn't realize you were talking about a "whisper type" cartridge and the .338 Whisper would be a great chambering, either way Dave Kiff of Pacific Tool can provide a 700 Bolt in any configuration with any size bolt head, diff. styles of fluting, dif. colours...I have some of his bolts in my 700s including my .300 Whisper.
 
2bad4u:
I made that suggestion to my friend, but I am trying to keep it simple,and inexpensive.

I have a totally unrelated question for u. Whats up with the "i love u max owner" thing on your profile? Just curious.

Well, what I suggested would be considered economical. Buying an Encore and then having a custom barrel made for it would likely be comparable in terms of money spent. Just a few moments ago you thought going with a bolt gun was a better idea than the Encore approach. Even if re-barreling a bolt gun was marginally more expensive, who cares? A couple hundred dollars spent shouldn't impact his decision making a great deal.

If it were me, I'd be willing to try an Encore. I've been wanting an Encore/Contender rifle for some time now, so that would personally appeal to me.

If expense truly is a consideration here, he's clearly not thinking things through here. There's nothing "cheap" about shooting .338 cal. match bullets. Hell, even load development would be a considerable expense.

As far as the Max Owner comment? Well, we were ### lovers in a past life. Hypnosis helped me discover this.
 
Thats the kind of thing I'm looking for Kombayotch! Right on!
Give me more info/ links etc.
I am trying to discourage my friend from going with the Spectre because there is just too much crap to modify!

Do you shoot the .338 Whisper?
What action etc?

I have a friend in Indiana who built one shortly before I left. It's a fun caliber, especially with a 9mm pistol can on the end of the barrel.

You can find loads for it on the Quarterbore forum, as well as on Silencertests, and maybe even Arf.com. Loads for .338 Specter would also be a good starting point as case capacity is pretty close. I kind of regret not going this way, but I already bought the reamer, headspace gauges and mags for .300 AAC Blackout and have the barrel on order. Kiff talked me into buying them when I was ordering some stuff since he had them on sale.

.338 Spectre is probably the worst possible option for this application based on the brass situation alone. If not the Whisper/Quiet route, I would neck up 6.5 Grendel brass before even looking at the Spectre. This is a wildcat I was toying with to allow me to use the 308 boltface for a subsonic round with similar case capacity to the .300 Whisper:

P1050258.jpg

Next to a .45 ACP case

P1050257.jpg

Next to a .308 round

That's just a rough prototype, which is why it's crooked as hell... it was just to play with and take measurements from before ordering/making a reamer. Your options are limitless when you start customizing.
 
Kombaya: Very nice looking round, I could go with one of those, but i think that a .338 bullet in the Br. case would be the Bee's knees, just use it in the right platform.
 
I've also considered .375 since there is a lot of 3/8" pipe/tubing I could swage bullets from, in addition to using .223 cases.
 
I can understand the 300 Whisper in a suppressed M4 type situation, but I don't totally understand the 338 BR type bullet unless it's going into some sort of CQB role? Please explain.
 
Why do you only see it as CQB? Do you mean specifically in an AR?

Out of a boltgun: you have a heavier bullet, with a higher BC, traveling at the same velocity. The trajectory is flatter (well, less of a rainbow) and it hits with more energy. There is also .510 Whisper, .50 Thumper, and other cartridges that shoot .50 BMG bullets at subsonic velocities.

Someone will inevitably point out the lack of expansion of the types of bullets being used, making the increased energy pointless. However, it isn't intended to increase the amount of damage on soft tissue, its intended to defeat higher levels of cover and body armour while still maintaining a low sound signature. The bigger bullets will do the same as the .30 cal bullets on tissue, but they'll do it after passing through stuff like a car door.
 
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Why do you only see it as CQB? Do you mean specifically in an AR?

Out of a boltgun: you have a heavier bullet, with a higher BC, traveling at the same velocity. The trajectory is flatter (well, less of a rainbow) and it hits with more energy. There is also .510 Whisper, .50 Thumper, and other cartridges that shoot .50 BMG bullets at subsonic velocities.

Someone will inevitably point out the lack of expansion of the types of bullets being used, making the increased energy pointless. However, it isn't intended to increase the amount of damage on soft tissue, its intended to defeat higher levels of cover and body armour while still maintaining a low sound signature. The bigger bullets will do the same as the .30 cal bullets on tissue, but they'll do it after passing through stuff like a car door.


I've never seen a ballistics chart on these types of bullets. For example, with a 300gr 338 bullet traveling at 1080fps, what is the energy at 200-300yds? and what is the drop on a bullet like that at that distance from 100yd zero? What is the barrel length on these types of rifles to burn that little of powder?
 
Barrels are typically 16.5" to be compliant with US law, unless they're willing to pay the NFA tax and their state allows SBRs.

JBM will give you the ballistics and the energy at whatever distance you want.
 
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