Gunsmithing The Cartmann.50 BMG Boreguide

[EricCartmann]

Soon to hit the market is the Custom Cartmann .50 BMG Boreguide. Only $199.99 at a Tactical Dealer near you. How important is your barrel to you? This device will help prevent unwanted damage to your bore due to improper cleaning techniques.

Each Bore Guide is a custom fit for your particular barrel. Just send us your barrel and some match ammo. We will custom make each guide to perfectly form to your particular barrel.
(shhhhh don't tell anyone that we use fireform brass, a hacksaw, debur it with deburring tools, and use 100 mph tape to keep it together)

Action Shot: Here is the Cartmann-50-BMG-Boreguide in action

Wow only 25 rounds through this barrel and look at the copper build up! The Cartmann Bore Cleaner will clean that barrel! It can be yours for only $99.99 for 16oz at a Tactical Store near you (Don't tell anyone that the Cartmann Bore-Cleaner is actually "Butch's Bore Shine").

Thanks to the custom Cartmann-50BMG-Boreguide, the Cartmann-Barrett-M99-Mod-32-Jack-Tatum is now ready for it's trip to the Desert

 

[Keith Johns]

Re: The Cartmann.50 BMG Boreguide

About cleaning 50s...
Do they require/benefit from more frequent cleaning than smaller calibers?


I rarely clean my 6.5Creedmoor. Once every 150-200 rounds.
How often should a 50bmg be cleaned? Any problems with build up at the crown?

Thanks to any advice.

 

[Dans40X]

Re: The Cartmann.50 BMG Boreguide

ask yourself this question-
If you're burning a 1/2oz,approximately 250+grains of powder per round-
Is the barrel going to foul faster or slower than shooting 40grains of powder?
DUH!!

If you have carbon build-up at the crown-
Remove the can or go back to the drawing board.

 

[EricCartmann]

Re: The Cartmann.50 BMG Boreguide

It's a new gun, and barrels do foul faster when new. I agree with Dans40x in that the 50 is so much bigger. Not only a lot more powder gets spit down the barrel, but that bullet is 640-750 grains! So it has a lot more copper to give to give to the barrel.

BTW, the Cartmann BoreGuide works great! I only see one other .50 BMG bore guide on the market and it goes for $65.

 

[Keith Johns]

Re: The Cartmann.50 BMG Boreguide

I wasn't comparing a 6.5Creedmoor to a 50BMG. I was simply saying I rarely clean my creedmoor, and itd be great if the 50 could be treated the same.
There are no 1/2" bores that burn 40grains Dan.
Everything's Relative.

The powder to bore size ratio would be comparable to a 7stw I guess.

 

[EricCartmann]

Re: The Cartmann.50 BMG Boreguide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Keith at PCR</div><div class="ubbcode-body">There are no 1/2" bores that burn 40grains Dan.
Everything's Relative.

The powder to bore size ratio would be comparable to a 7stw I guess. </div></div>

I am not Dan.. but I thought I would put in my 2 cents.

It might be all relative as far as copper build up and powder per square inch goes, but the thing is you have more square inches. Bigger rod, bigger patches, and more force of the rod is needed.

Fact: The picture above of the "wet patch" above is what the barrel looked like after 25 rounds.

You analyze this however you want to.

Also not all barrels foul evenly. My Savage .308 fouls really bad at about 100 rounds, enough to affect velocity. The dirtier the Savage gets, the hotter the rounds get, and I get signs of overpressure in the cases when gun is dirty. My .308 Remi 5R on the other hand has almost no fouling at all even after 200 rounds (patches still relatively clean)

 

[Dans40X]

Re: The Cartmann.50 BMG Boreguide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Keith at PCR</div><div class="ubbcode-body">There are no 1/2" bores that burn 40grains Dan.
Everything's Relative.

The powder to bore size ratio would be comparable to a 7stw I guess. </div></div>

Keith/Always Learnin'-
.499"/.510" bore 40gr cases-don't rule out pistol cartridges.
Powder to bore ratio was comparing 6.5 Creed(40gr) to 50BMG(250gr).
Your guess of the 7mmSTW isn't in the ball park!

Hopefully you aren't the brains @ PCR.
(glueing hand files into stock fore ends)

EricC-
Fit an"insert"(alum or delrin) between rod & your 2 cut off 50BMG cases to ensure cleaning rod clearance in bore.
Speed/100mph tape is aluminum backed.
Your duct tape will get slimy once solvents leach in.
A drop of solder may suffice!

 

[Keith Johns]

Re: The Cartmann.50 BMG Boreguide

Edited!

Dan
Ok not counting pistol cartridges and the 50beowulf.
You know what I meant.

If going by the area of a given bore diameter, and excluding rifling...
A .338 bore with 115 grains of powder going down it would be somewhere close to a .50 bore with 240 grains of powder going down it.(being about half)
Or a .284 with 80gr of powder(being about 1/3rd). Kinda like a 7stw

Thats what the math came up with for me, if I did it right.


You must have a real way with the ladies Dan

 

[The Mechanic]

Re: The Cartmann.50 BMG Boreguide

My 10/22 is dirtier to shoot than my EDM Windrunner.

 

[Jabronie]

Re: The Cartmann.50 BMG Boreguide

verynice! I have to laugh my ass off this commentary is so south park very nice!

 

[Keith Johns]

Re: The Cartmann.50 BMG Boreguide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: DANS40X</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Keith at PCR</div><div class="ubbcode-body">
The powder to bore size ratio would be comparable to a 7stw I guess. </div></div>


Your guess of the 7mmSTW isn't in the ball park!
</div></div>


Unless my math is wrong, and hell it could be

, a 7stw(.284) has about 1/3rd the bore area as the .50 does, and uses about 1/3rd the powder charge.
(If the 7stw is burning around 80gr of powder. And if going by area of a bores circumference, excluding rifling to simplify things)

I guess thats why I said 7stw. The bore diameter area to powder charge ratio seems close, the 50bmg is just 3x higher on both numbers.
Again, just looking at bore diameter <span style="text-decoration: underline">area</span> and <span style="text-decoration: underline">powder charge</span>.


Does the 50BMG foul like a 7stw? It looks like a blown up 30-06

And I might make a boreguide somewhat like yours Cartman. Using a case in front but then a turned polymer guide to go inside.

 

[sgtkeebler]

Re: The Cartmann.50 BMG Boreguide

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Keith at PCR</div><div class="ubbcode-body">About cleaning 50s...
Do they require/benefit from more frequent cleaning than smaller calibers?
Thanks to any advice. </div></div>

In my experince they dont require any frequent cleaning. Just keep adding CLP and it will continue to run we had over 10K rounds through 2 different 50's in a day no problems. Gotta love that M2