[ejc]

The barrel measured .357 inch. While I haven't shot the gun yet, I suspect having a barrel that large will not be real accurate. Giving the purpose of these pocket pistols, it really doesn't matter. It will be accurate enough for short range encounters which is what I bought it for.

If any of you have checked your barrel, what size did it measure? Just curious if this is the norm of it it is unusual.

Thanks.

E. J.

 

[Maximumbob54]

You might call them and ask for a new barrel. I hope you had the right alloy as you may have been getting "spring back".

 

[ejc]

Actually, I used a slug produced by LBT that were specifically made for slugging barrels. A few years ago I slugged a barrel on a new gun I had bought and it measured .458 on a 45 Colt gun. The company gave me some trouble over the barrel so I had a gunsmith measure the barrel and he got the same dimension I did so I have a lot of confidence in the LBT slugs.

E. J.

 

[glenwolde]

There's a member here named Ranch Dog who figured that out and designed a bullet mould for Taurus .380's

http://www.taurusarmed.net/forums/700s/61012-tcp-738-reloads.html

 

[ejc]

Glenwolde, I had read that thread and saw the picture, and just missed the bore diameter. Sounds like it is pretty typical so I won't worry about it.

Thanks.

E. J.

 

[olfarhors]

ahhh, Ranch Dog amy be the one to really answer this but!
I seem to remember that for the 380 cartridge this is about right.
now as I seem to remember that 380 being mainly a Europian made weapon up until just a short time ago, that many different manufactures had barrels that differed in diameter, and so for safety the 356-358 was kind of adopted for a standard diameter for 380 caliber weapons?
there is a lot of variation in actual diameter from manufacture to manufacture in different calibers actually, most shooters gop about using the firearms with no problems as long as they don't know that!-LOL

 

[Ranch Dog]

Actually, Taurus is using the same barrel stock for all their like caliber firearms. The 9mm Luger, 380 Auto and 357 Mag (handguns and long guns) are all the same. Same with their 45 caliber firearms; 45 ACP, 45 Colt, and 45-70 Govt. all the same.

 

[olfarhors]

Actually, Taurus is using the same barrel stock for all their like caliber firearms. The 9mm Luger, 380 Auto and 357 Mag (handguns and long guns) are all the same. Same with their 45 caliber firearms; 45 ACP, 45 Colt, and 45-70 Govt. all the same.

OK MR DOG, you may need to expand on this as i think i got lost?
is this relating to the bore diameter of the gun or was it in reference to something else that i missed??
You gotta type real slow cause I get lost easy!--what can i say-- a public education!!-LOL
SO are you saying that for example the 380, 9 MM, 38 Super, 38 Spl, 357 mag, all have the same bore size--.357 roughly?
and that only the chamber dimensions are different??

 

[Montkun]

Kind of what it sounds like to me if i'm reading this right.

 

[Ranch Dog]

SO are you saying that for example the 380, 9 MM, 38 Super, 38 Spl, 357 mag, all have the same bore size--.357 roughly?
and that only the chamber dimensions are different??

I've made impressions of the 380 Auto, 9mm Luger and 357 Mag and the barrel groove and bore dimensions are the same only the chamber is different. Same for the 45 ACP, 45 Colt and 45-70 Govt. The barrel groove and bore dimensions are common between the cartridges. That tells me that they use common barrel stock.

There was a thread some time back in the Millennium Pro forum about the 45 ACP pistols always falling short on velocity. It was suggested that the barrel length played into it. I didn't believe that was the case because that difference is easy to calculate. Once I had the impressions of the various 45 ACPs and knew the dimensions, I was able to digitally duplicate the velocity performance in Quick Load knowing that the barrels where over diameter. In other words, when the actual barrel dimensions were entered in Quick Load, the actual FPS seen over the chronograph matched the projections. The reason some of the these cartridges are not matching ammunition velocity expectations is that the barrels are "big" and combustion gasses are being relieved around and out the barrel. This is also a common method manufacturers use to rapidly reduce chamber pressures which I speculate is related to efforts to minimize product liability issues. The best visualization of this is from my 25PLY (25 ACP). This is a cartridge that the barrel could have been cut to spec as there is nothing else they manufacture, other than the Wizard in 25-06, but the barrel was cut the same amount over bore and groove. Here is the appropriate jacketed bullet, .251", pressed midway into the barrel.

Taurus is not alone in this practice, every manufacturer I've measured in my cast bullet work does the same. Taurus is different in that they at least cut the chamber exactly to the SAAMI/CIP spec. Many others cut the chambers large as well.

The Taurus pistols will lend themselves well to cast bullet work in that a bullet can be tailored to the need. With a properly sized bullet, cast bullet accuracy will always trump jacketed bullet accuracy

 

[GreenWolf70]

Very interesting information. Good to know their are people more anal than I am, and with the means to do it.

 

[olfarhors]

I've made impressions of the 380 Auto, 9mm Luger and 357 Mag and the barrel groove and bore dimensions are the same only the chamber is different. Same for the 45 ACP, 45 Colt and 45-70 Govt. The barrel groove and bore dimensions are common between the cartridges. That tells me that they use common barrel stock.

Thanks for information, nice to learn something new everyday!

 

[Ranch Dog]

I want to add a "By the way guys"...

Don't do this at home! I have the equipment and experience working with this stuff, I know that I could have damaged this barrel without much additional effort. I even chose my shortest barrel and least expensive Taurus for this demonstration just in case I goofed it up. Need I mention the consequences of leaving this obstruction in the barrel. Strange things happen at any point of time and doing this to your firearm is begging for disaster on all fronts.

Okay, that said. The one barrel fits all is a great idea is far as I'm concerned. Taurus can direct all their quality control effort on fewer components. They can focus on a single set of dimensions and cut off the length of stock they need. I say "well" done.

As a designer of bullets, the 9mm Luger does throw me a bit of a curve dealing with the .351"/.358" barrel. I've dealt with it in this fashion with my TLC356-135-RF design:

• I made it a gas checked bullet. The shank is cut for the 35 caliber rifle check (.359"+ outside diameter) rather than the 35 caliber pistol check (.356"+ OD). This has been a handy move in that Hornady, the sole supplier of commercial checks, has ceased production of all pistol checks.
• The 9mm Luger has a tapered chamber. A .358" bullet would not dependably chamber at the step. The bullet diameter plus the case walls would create too much case bulge delivering too tight a fit. What I designed in the bullet was a front driving band and first body band of .356" with the second two body bands at .357". In other words, a tapered bullet.

How I prep the bullet is:

• Dip lube the bullet with Alox and set it out to dry.
• Run it through a .357" sizer to true the body bands.
• Snap on the gas check and run it through a .359" sizer.

This gives me a tapered bullet without much case bulge that is tailored to the spec chamber and "optimized" for the Taurus over-diameter barrel.