tp555 300 whisper barrels

[SwampF0X]

Hello, I'm thinking of getting one of tp555's 300 whisper barrels. I would like to hear from anyone who has one.

How's accuracy at subsonic speeds?

Special tips and load data? I want to use heavy subsonic projectiles with a suppressor.

thanks,
swampf0x

[oregonshooter]

Can't help now, but give me a few months and I'll be doing exactly that. I decided to build a dedicated subsonic gun and shoot only 240 SMK, but I did get his 3way block for options.

This is a slow forum, but maybe someone will help us both out on the learning curve. :)

[Spook]

I still have one he built for me from a stainless Brux blank I sent him a long time ago....shoots subs very,very nicely.
I dont think anyone has any worries dealing with TP555, the guy knows his stuff.

[rv10flyer]

I have been very pleased with my barrel and 3-way gas block. I’m still working up loads so I don’t know the ultimate accuracy potential but I am happy with the results so far.

His response to emails and questions were always prompt and helpful.

If you order one of his gas blocks I would recommend ordering a gas tube from him as well. The adjustable gas block requires a gas tube a little shorter (5.75” OAL IIRC) than a standard pistol length gas tube. It is a PITA to shorten and bend a pistol length gas tube (at least it was for me and I didn't have the tools to properly flare the end).

[oregonshooter]

and a case guage! I've been very happy with his CS and willingness to answer newb questions. From the name of the company he is a machinist first and gunsmith second. Machinist are by nature perfectionists, gunsmiths not so much.

[SwampF0X]

He said he would assemble my upper for me for a modest $20

Why do I need a case guage? What is a case guage?

swampf0x

[Scalce]

He said he would assemble my upper for me for a modest $20

Why do I need a case guage? What is a case guage?

swampf0x

Have you reloaded other catridges before?

It is a gauge that tells you how to set your resizing dies so they resize the case enough but not excessively which will shorten your case life.

Usually these are based on SAAMI specs and are general.

For 300 Whisper or other custom barrels, you can have the smith cut you a gauge which is actually bored with the same reamer that your barrel is cut with.

This is more of a chamber gauge which is a perfect match for your barrel and almost a necessity when initially forming 300 Whisper brass and resizing after fire forming.

A custom chamber gauge may also have the beginning of your rifling so you can set the OAL of your reloaded rounds to be jammed in the throat, a small distance from the throat, or have a slight jump.

In an AR you will be limited by the magazine length for the OAL so some barrels have a shorter throat which can be a good or bad thing depending on if you are aware of it and know how to utilize it.

[tp555]

Case gages are very useful.I bought another 30/221 reamer from PTG.The Clymer reamer is based on the 1.4" OAL case.The PTG is based on the 1.35" OAL case.Longer case won't work in the shorter chamber.Most first time brass forming is from once fired brass.Mil brass is thicker and tougher.The problem is usually the shoulder neck area.The case has a very short shoulder but the forming leaves a radius here.It hits and causes problems.Once fired its good.The Redding dies need a good bottoming out to work on a Dillon press.So If the round drops into the gage it will work. Mil brass had neck separation after 5 reloadings for me.I would anneal the neck area after cutting to 1.4".This is a lot of work.One guy bought a barrel from me and had Teppo Jutsu build the upper.It wouldn't fire the ammo he bought from someone else.He was unhappy.Trash the upper after much $ or trash the ammo.Don't know how it turned out.

[SwampF0X]

I've reloaded other catridges but I've never used a case gage. I just load to the recommended OAL and let it be.

Once I shoot up all my 223's I plan to let someone form my brass to 300 whisper. From there I'll load my own according to info I find on this site.

If tp555 builds my barrel and assembles my upper (and he probably will) Who should I get to form/size my brass so that I won't have any problems?

thanks,
swampf0x

[oregonshooter]

For accuracy you need to know where your Datum is in relation to the bore.

There is too much to it for me to explain in print and I'm new to accuracy loading myself, but I can suggest a great book on the subject.

http://www.amazon.com/Handloading-Competition-Making-Target-Bigger/dp/096269259X

[Scalce]

I've reloaded other catridges but I've never used a case gage. I just load to the recommended OAL and let it be.

Once I shoot up all my 223's I plan to let someone form my brass to 300 whisper. From there I'll load my own according to info I find on this site.

If tp555 builds my barrel and assembles my upper (and he probably will) Who should I get to form/size my brass so that I won't have any problems?

thanks,
swampf0x

The OAL has nothing to do with how much you are bumping back the shoulder.

While most standard rifle case gauges can be used to check the OAL of a case, the main use is to make sure you have the proper amount of body and shoulder sizing to allow the case to chamber in a SAAMI spec rifle chamber. The gauge also allows you to not overwork your brass by bumping the shoulder back too much which potentially shortens the case life.

Even if you have someone initially form your brass, you will still need to full length size your brass for a semi auto or at least neck size for a bolt gun. You may also have to occassionally full length size for a bolt gun if the case gets hard to chamber and extract after a few firings.

I would say that you should have tp555 make you a chamber gauge along with your barrel.

This will allow you to send it to whomever forms your brass so there will be little chance of the brass not being sized correctly.

You will also have the gauge for your own use when resizing the fired brass.

Ask tp555 but I bet he will advise you to form only commercial 223 brass and to shy away from milsurp as it may have chambering issues because of a more rounded shoulder during initial forming.

I hope you don't think my posts are meant to insult you as I am just trying to give you as much info as possible so you can enjoy shooting your rifle.

This catridge is still technically a wildcat and there are many variables such as gunsmiths, chamber reamers, throats, cases, bullets, dies, and more that can be a factor.

I am still learning alot about it myself but I think that is half the fun.

[SwampF0X]

No I'm not insulted in the least. That helped me understand things a little bit clearer. I have no problem full length sizing my brass. I don't have any Mil Surp brass. Most of it is new Win. The rest is Federal and 2 boxes of Remington.

OK just to make sure I'm following, I should:

a. have tp555 make me a case gage along with my barrel
b. send my brass and case gage to someone for them to form (Who?)
c. full length size my brass with Redding dies (tp555 recommended) once I get it back

Should I have tp555 use his old reamer or the new shorter one?

Then what? Am I ready to go shooting after I load some up? Most of my brass will only see maybe 2 loadings. I don't shoot a lot and I bought enough brass to defend my home in case of invasion :D

thanks,
swampf0x

[oregonshooter]

He will cut it from the same reamer (1.350) that he does the barrel.

You can fire-form your brass yourself. My plan (anyone tell me if this is wrong) is to fireform then use my .308 mic (http://www.midwayusa.com/viewProduct/?productnumber=574297) to find the datum point (should work since the neck up is .308 right?) and reset the shoulder .002" like I do on my .308 gun. Use the case guage as a double check.

You should hear the shoulder hit the case guage as you drop it in and then have the cartridge flat on the back end to know you are in the right spot if I understand the process.

If the case guage has the bore dia at the end, I'm guessing that you can actually set OAL to visually touch where the lands are in the barrel for a perfect shoulder setback and nose to lands fit.

I believe that is why tp555 is going to the 1.350" reamer because you will be able to get up to the lands where you can't on a 1.400 chamber because of the AR15 mag OAL limit.

I just hope mine is in 1.350" :)

[tp555]

Let me know which reamer you want used on your barrel.The default is the 1.4" clymer.

[Scalce]

a. have tp555 make me a case gage along with my barrel
b. send my brass and case gage to someone for them to form (Who?)
c. full length size my brass with Redding dies (tp555 recommended) once I get it back

Should I have tp555 use his old reamer or the new shorter one?

Then what? Am I ready to go shooting after I load some up? Most of my brass will only see maybe 2 loadings. I don't shoot a lot and I bought enough brass to defend my home in case of invasion


a. Yes, definately worth the money.
b. I wouldn't see why you couldn't include your chamber gauge as you will most likely ship your brass in a flat rate anyway. I am not sure if the person would change his current settings to suit your chamber but you can always ask. I do not have firsthand experience but it seems there are a few people here that offer brass forming services. Your best bet it to ask around.
c. You will only need to FL size your formed brass after it is fired and the chamber gauge can be used to set it up properly.

I would say to go with the 1.355" OAL reamer as that seems to be more common now than the 1.4" which I think was a slightly older spec.

You should be able to add a primer, powder of choice, and bullet once you get your formed brass back and be ready to test some loads.

Keep in mind that you may always have some type of slight chambering issue on newly formed brass that have not been fire formed to your chamber.

This could be anywhere from the round not chambering completely and the bolt not going into battery which stops the firing pin from hitting the primer or just a slightly rounded shoulder that makes a chambered, but not fired round hard to extract.

You can always test the rounds in your gauge but rounds being cycled in a semi auto if the real test as there are more real world factors at play.

[SwampF0X]

Let me know which reamer you want used on your barrel.The default is the 1.4" clymer.


Which one is recommended for heavy subs?

swampf0x

[oregonshooter]

Which one is recommended for heavy subs?

swampf0x

+1

For an AR barrel with OAL issues cause of the mag, I'm assuming the 1.350 is being used to allow getting the bullet closer to the lands?

tp555,
We both need educating! What is the case trim length with the 1.350 and why would anyone want it?

[tp555]

I make stuff.You guys get to play with it more than me.The 1.35" is JDJ spec.What does he say? Typical trim is .010" shorter.

[oregonshooter]

Having done a little more reading, my conclusion is that if you are loading resized .223 like me there is not much advantage to a 1.350 as it's best for 221 brass that does not flow out past 1.350 when resized. A reduced chamber length and a long case can equal kaboom pretty fast and the advantage of a supported neck on a shor bullet is over shadowed by this IMO.

Make mine a 1.40 for safety reasons please!!

[Scalce]

Having done a little more reading, my conclusion is that if you are loading resized .223 like me there is not much advantage to a 1.350 as it's best for 221 brass that does not flow out past 1.350 when resized. A reduced chamber length and a long case can equal kaboom pretty fast and the advantage of a supported neck on a shor bullet is over shadowed by this IMO.

Make mine a 1.40 for safety reasons please!!

Interesting

So I am assuming people who trim to 1.355" have a 1.4" chamber?

See why you shouldn't listen to my comments? :grin:

[oregonshooter]

Yes.

1.355 in a 1.350 chamber would be very bad, very bad. :)

.050 back from the actual chamber length is a good rule of thumb from what I'm reading.

If your chamber is longer you get a bit of unsupported neck which can affect accuracy (not consistently indexed) but for an AR and the expected accuracy from it, I don't believe it outweighs the potential for high pressures that will develop when your casings grow (flow rates change with # of reloads even if you trim every time) and then have no place to go in the chamber that is too short, locking the bullet in and raising the pressure to unsafe levels.

The SSK 1.350 chamber is mostly because .221 Fireball brass does not resize past 1.355 well. Shorter chamber means you can cut the case shorter, not that the OAL will change much as the magazine is the limiting factor and bullet setback is not an issue with a low pressure round like the 300 Whisper.

Since I'll be using .223 brass the 1.400 makes more sense to me.

Now, all that is just my WAG. I've yet to read anyone that says one way or another and there does seem to be a lot of guess work on this Wildcat so I'll stick with a safer 1.400 since I like the extra wiggle room it gives me and don't think accuracy is going to suffer to a point I can see it in my AR15 SBR setup.

If any of the experienced guys read this, please point out my errors in thinking!

[Scalce]

See the thing that confuses me is I have never heard of anyone trimming below 1.35" which leads me to think that the reamer measurements are not exactly matched to the case OAL like we are assuming.

[Hoser]

A touch too short isnt a big deal. Anything from 1.340-1.400 in a 1.400 chamber is fine.

We arent shooting benchrest here.

[oregonshooter]

We arent shooting benchrest here.

Yeah, I came to the conclusion that it would not matter and was reading too much BR info. Those guys are plain nuts! :grin:

[SwampF0X]

Ok, I need a tp555 barrel with a 1.4" chamber?

I need to send my once fired 223 brass and 300 whisper case gage to Hoser and have him form and trim it to 1.355

When I get my brass back, I am good to load em' up? Only need to full length size them for the second re-loadings?

Now...............If I SBR it, how short can the barrel be, without interfering with the gas system and leaving enough barrel in front of the gas system to thread it for a suppressor? I think I'm gonna go with a 9mm pistol can. If I want to shoot supersonic rounds I have plenty of other rifles for that.

swampf0x

[Hoser]

When I get my brass back, do I need to full length size it in my Redding dies or am I good to load em' up?

Just load them and go.

The shoulder is bumped back just fine and the base is completely resized.

[Scalce]

Now...............If I SBR it, how short can the barrel be, without interfering with the gas system and leaving enough barrel in front of the gas system to thread it for a suppressor? I think I'm gonna go with a 9mm pistol can.

I am guessing that you can get down to somewhere around 6-7" to physically allow room for threading with a pistol port gas block in place but do you really want to go that short?

I know there was a recent debate of why go with a 10-10.5" when shooting only subsonic loads with what is essentially a pistol cartridge but I think the shortest length discussed was maybe 8".

I'll try to find it.

[SwampF0X]

Would there be any drawbacks to using a 8" barrel? What is the best length for a 300 whisper and why?

swampf0x

[oregonshooter]

Would there be any drawbacks to using a 8" barrel? What is the best length for a 300 whisper and why?

swampf0x

tp555 told me 9" was OK for a heavy suppressed only setup like I'm building. I believe you are looking for the same, but mentioned trying supersonics. 10.5" is the best for both.

I would not go the extra 1" shorter, although I think he did say he had made one 8" in a post here but never heard how it tunred out.

[SwampF0X]

More than likely I'll be shooting subs almost all the time. But IF I ever have to grab my rifle and run, I would like to have a few mags loaded with supersonic ammo to use on bad guys

swampf0x

[mstarling]

SwampFox,

I have not checked in here for a while as I've been playing with a 6.8 lately.

I bought one of tp555's stainless barrels in October 2009 I believe. Is a 16" mounted on a BRO upper/lower. Did order a chamber gauge at the same time. The chamber gauge is a wonderful thing! Get one!

I did not want to go through the Form 4 hassles of a shot bbl again (Sheriff has changed and is not Class III friendly) and I wanted to hunt with the rifle ... so I went with a 16" tube.

I do use mil brass as I have a bunch of it ... and the chambering gauge is necessary to figure out what pattern is needed to properly form brass.

Tp555 is a straight shooter who does lovely machine work. You can depend on him!

Mike