Why take a chance on the reamer when making a custom rifle?

[Lefty7mmstw]

If you go with a SAMME reamer that's all you need. I highly recommend the SAMME reamer with Standard free bore and throat Just make sure that the smith knows
not to substitute with another reamer. (The Manson reamers are my favorite) and to make sure I recommend that you buy the reamer yourself from Dave so you will get the right chamber.

The 8 twist is a little fast for the STW in my opinion unless you are shooting 175 grain bullets or more. But it really has nothing to do with the reamer.

I recommend a 1 in 9 for bullets 168 and down because the STW can produce some very high velocities and bullet jackets can suffer if rotated to fast. also if you want a Shilen get the select match only.

Sounds like you are on the right track.

J E CUSTOM

I believe he's ordered the reamer from Brownell's... so a good source that shouldn't sub out a non- spec reamer...
I plan on shooting everything from 140 Nosler bonded to 195-200 grain bullets in the rifle. I know 120-130 grain and possibly 140 grain match will blow up on a 8" twist, but that's the price you pay for the ability to spin the big hunks of lead. It's really no different than my 5.56 ar 9" twist... A 40-45 grain pill will likely have issues but a 68-75 gr. match will spin well.

I was hoping to get a 4 groove blank but it came in as a 6 groove ( I guess 6 is still standard for Shilen with the 8" twist)... Possibly a bit better as far as bullet stress but worse for throat wear, not??

 

[Clark]

I have a couple dozen reamers for building my own rifles and only a couple custom reamers ordered; 223 and 6mmBR.
The rest are handguns and deer cartridges. I can use sloppy SAAMI specs on those.

Then there are the wildcats, which no one but me would ever care about.

 

[J E Custom]

[QUOTE= I can use sloppy SAAMI specs on those.

Not trying to start a argument, but SAMME spec. reamers are not sloppy. They are built to a specification that forces the ammo manufactures to hold there dimensions to the standard.

A SAMME chamber is designed to handle most brands of ammo within SAMME safe pressures.
Chamber quality depends on the quality of the reamer and the Gun Smith that cut it.

After fire forming, any chamber can be sloppy if the brass is sized to much when reloaded. so the problem comes when loaded with the wrong die setting.

I recommend fire forming in any chamber and then sizing only enough to let the bolt close and no more. This will keep the brass fitting the chamber and increase brass life.

Tight necks, throats, free bore and any modifications to a SAMME spec should only be made by an experienced Reloader to avoid potential problems.

A SAMME chamber can be very accurate (Well under 1/4 MOA) If loaded correctly.

Just trying to clear up the myth about SAMME chambers Being bad. It is up to the Reloader to get the most from a well cut chamber no matter what kind it is.

Just my opinion

J E CUSTOM

 

[shortgrass]

+1 How many times have we read or seen with our own eyes cartridge brass fired in one SAAMI speced chamber that won't fit in another chamber cut with a SAAMI speced reamer. That is when we hear the whinning of the uninformed begin! The reamers I get from Manson and JGS that are SAAMI speced are all minimum sized. They are far from "sloppy". I've seen an instance or two when factory made, SAAMI speced ammo has refused to chamber when a mimimum speced Manson or JGS reamer is used to cut the chamber and the headspace is set to the minimum dimention. Like was posted earlier, many if not most times there's no reason "to reinvent the wheel". The main alterations I personnally like are a tighter neck dimentions (diameters), as even minimum SAAMI can be quite generous. I prefer a "NO TURN NECK", but even doing that can bite you in the rear, sometimes. Too many don't recognize all the factors involved. Rifles with 'special' or obscure chamberings are far more difficult to sell later, should you want to. The reamer makers love all these special orders they're getting, lately.

 

[Mikecr]

I fill out a reamer print, order the set(including finish, roughing, sizing, pilots, go/no gages), and hold it to send with my barrel/die blanks for finishing. These are my tools, and I expect them back in good condition(for future barrels).
When I sell a gun, the reamer set, dies, bushings and gizzys go with it.
The barrel finisher would typically mark the barrel with something like "6BR IMP .267NK"

Where I buy pre-built bolt guns, it's worked out all right, provided I still use custom dies (fitted from fire formed brass). I'm talking something like a Cooper or McMillan, and where I won't be needing to replace the barrel frequently.
I'm as happy as can be to do this, if I can, as it saves time and money for sure.

 

[AZShooter]

Not to beat this to topic to death but here is an example of where a custom reamer would have helped:

http://www.longrangehunting.com/forums/f28/wsm-casing-life-155249/


The OP is getting split necks with the 270 WSM brass after two firings.

Another poster said he noticed the Winchester brand WSM cases have thinner necks. Combine the use of what some called a sloppy SAMMI chamber with a FL die and the brass gets brittle fast. I suppose one could argue the chamber is not at fault but the brass is the issue. True but you are not going to get Winchester to change their brass dimensions. One could also argue don't use Win brass, also true. BUT if Win brass was all you could get then a tighter neck dimension would be the only option.

Now if a reamer was made to accommodate that thinner brass neck the necks would last longer......

I asked the OP who made the rifle and haven't heard back. It would be ironic if it was a Winchester rifle.