This page gives you some examples of barrels customized by me, Mike Bellm. A little about my approach to the work I do.  All chamber and crown work I do 

is performed with the principle of machining the barrel around a straight line mandatory with everything centered and square to the bore! 

 NO floating reamer holders and NO piloted crowning tools are used, neither of which can hold true concentricity with the bore!

(True confession time. Due to the runout in many of the TC factory .357 Magnum chambers interfering with the throat reamers, I HAVE found it mandatory to use a floating reamer holder when rechambering the factory .357 Magnum barrels to .357 Rem. Maximum.) 

 It takes only a modicum of observation and thinking to see there is no way a pilot can consistently maintain alignment of a cutting tool, be it a chamber reamer or a crowning tool. This goes counter to "common wisdom" and generally accepted practice, but with nearly 30 years of barrel work to back it, pilots, and especially floating reamer holders simply DO NOT maintain concentricity.  

 Center the muzzle and the bore of most any production or custom barrel chambered in a manner relying on a pilot for alignment, and you will nearly always see very measurable runout in the mouth of the chamber.  You will also see the throats are misaligned with the bore, sometimes very seriously misaligned, even by some of the best known benchrest 'smiths.  My process for recrowning with a precision 11 degree assures crown is cut cleanly centered and square with the bore without marring the barrel's finish. Precision recrowning is done starting with turning a sleeve mounted on the barrel concentric with the bore. 

The crown is referenced off the bore, not the outside of the barrel.  When chambering or rechambering the bore is centered in the lathe referenced off the point in the bore where the throat is to be cut, co-axial with the axis of the lathe. Where possible, chamber body is first lathe bored concentric with the bore before any reaming is done, assuring both the throat and chamber are inline, co-axial with the bore.  All rim counterbores are lathe bored, not reamed.  All throats are cut as a separate, last operation, minimum diameter, long leade angle, centered with the bore.  

 I DO NOT use SAAMI specs! If you want accuracy and best case life, SAAMI specs are garbage. I craft chambers around "real world" ammunition and size dies, not drawings. All dies I supply with barrels have been checked for dimensional compatibility.  Anyone can buy a reamer and cut a chamber, but few if any go about chamber work the way I do, crafting the chamber around the cartridge, not a paper print. 

Braked TC factory .460 S&W; 15" stainless Encore barrel. Here is an example of the Bellm machined in muzzle brake in an Encore handgun barrel.


Close up of my machined in brake..... a very easy to shoot Whelen!


Try this one on for size!  .45/70 Bergara barrel rechambered to .458 Lott cut to 18", 4 port Bellm muzzle brake, picatinny rail 6-screw, drilled for handgun forend and front rifle forend screw hole tapped out to 10x32 and sling stud installed, TBOSS cut at breech end, open sights installed.


.357 Rem. Max. relined 10" blued Contender/G2 barrel.


                                            This is a used Contender barrel I neatly, cleanly relined to .35 cal., 

                                               precision recrowned, and rechambered to .357 Rem. Maximum.  

                                                          This will be a real "shooter" !  A superior Max!

Can't tell if there is a liner inside or if it is all one piece!  

 Precision 11 degree target crown.


.300 Whisp-R Improved 12" Contender/G2 barrel & dies.  

None currently available except as relining conversions. 


                                                                       .300 Whisper round, left, .300 Whisp-R Improved, right.

10," 12," and longer lengths as available chambered to the Improved version of the .300 Whisper, either rimless, or rimmed cases made from .357 Rem. Max. brass. 

.300 Whisp.-R Imp. is what the original .300 Whisper should have been designed as in the first place. The shoulder diameter is increased to .370", and the shoulder angle is a much more substantial 40 degrees. The rim of the parent .357 Rem. Max. brass assures positive headspace. 

Shoots commercial .300 Whisper factory ammo, legal for Illinois handgun deer hunting. 

The extractor is set up to accommodate both rimless ammo made from .221 FB brass or .357 Rem. Max. brass, both of which are available from me preformed & trimmed to length for this barrel on special order. Or, form your own cases.

.357 Max. brass must be annealed before forming

No fireforming is required. Just load and shoot. 

.300 Whisp-R Imp. Stainless fluted 19 1/4 in. carbine barrel. 

This is an example of what can be done stubbing a barrel and also expanding on the .300 Whisp-R Imp. cartridge it is chambered for. 

Unique stainless Pro Hunter barrel "stubbed" into a blued Contender barrel. Beautiful deer sniping barrel used as a handgun, or use with buttstock as a carbine.

Click the link immediately above for a page dedicated to this neat little barrel.


More details about .300 Whisp-R Improved.

my spelling seems to have gone down the tube since I got on the internet, but, no, that is not a misspelling of Whisper. 

What I have done is what the "ballistic genius from Ohio" should have done to the .221 Fireball case in the first place. That is, establish a more pronounced shoulder to headspace on by increasing the shoulder diameter approx. .010" to the same diameter as the similar .223 Rem. based rounds such as .223 Rem. Imp. and the TCU's like the once popular 7mm TCU. And, the shoulder angle has been made the more abrupt 40 degrees like the TCU's.

Those shooting the standard .300 Whisper or those familiar with the round are aware that once you bump the neck diameter of the Fireball case to .30 cal., there is not much of a shoulder left. 

Go figure...... neck diam. is about .330," shoulder diameter .360" and change, difference about .030-.035." Divide that in half for the radius, and you have a shoulder that is only about .015 to maybe .018" wide.... NOT MUCH! 

While adding about .005" to the width of the shoulder is not much either, that combined with the more abrupt shoulder angle is a definite improvement in supporting the case against the blow of the firing pin. 

Also, what I have done is cut a rim counterbore for .357 Rem. Max. Thus you have the best of all worlds with this type of cartridge. 

You have a better shoulder to headspace on, the back up headspace point at the rim to regulate how much the shoulder can collapse when the firing pin hits the primer, and the convenience of shooting either rimless or rimmed ammo interchangably. 

The reason for wanting to still be able to shoot rimless ammo is largely for those good folks in my home state of Illinois where this guy grew up as a pig farmer weilding a razor blade on the back end of boar pigs starting at about age 8. Thankfully, I learned to exercise more finesse carving steel than I did carving out supper. So much for the more colorful side of my history.

In Illinois, the .300 Whisper and the .30 Bellm are the only two bottleneck cartridges grandfathered in as legal handgun deer hunting rounds. There are those who are more enthralled with the mystique of the miniscule Fireball case and its practicality compared to the larger and somewhat faster .30 Bellm. 

Thus I have crafted the .300 Whisp-R Imp. so that standard .300 Whisper ammo can be fired in the chamber, making it legal for use in Illinois for deer. The letter of the Illinois regulations stipulate what ammo can be used, not the chamber. So if you have a box of commercially loaded Cor-bon ammo, you are "good to go" hunting deer with it. 

For other purposes, or if you want to stretch the envelope a bit, you can make cases out of .357 Rem. Max. brass, which I also make and supply if you want to use the rimmed version. 

Accuracy is the main interest, and with my throating, expect these barrels to be tack drivers that are very comfortable to shoot. 

While Illinois deer hunters were first in my mind for this chambering anyone from any state that is interested in diminuitive, high performance rounds like this will certainly enjoy it.

.358 Bellm 14" blued Contender barrel with my machined in muzzle brake and 6-screw Weaver base on.


This one started life as an excellent used .35 Rem. Maximum TC factory barrel with its rather useless .4" long forcing cone that I rechambered to .358 Bellm. The longer .444 Marlin based chamber cuts out all of the original factory forcing cone, resulting in a new and proper throat that I tailor for both jacketed bullet and cast lead use.  .358 Bellm is also an excellent "fix" for problematic .35 Rem. barrels. .358

 Bellm has a more substantial shoulder to headspace on, a rim to backup headspace, and stronger brass than the thinner .35 Rem. brass.  Compare to .358 JDJ, but uses standard .358 Winchester dies. Ie, no custom dies required.

  It is superior to the JDJ also in that its capacity is more in keeping with the pressure limits imposed by the Contender/G2 and the powders that work best with this bore size and the bullet weights appropriate to 14" handgun velocities.  It shines with H-322 which is too fast for best results in the larger JDJ rendition of a necked down .444 Marlin.  

 This is a super hunting round for larger game, and .358 Bellm is the optimum "fix" for .35 Rem. barrels.  With my neat, clean, precise muzzle brake machined into the barrel and its internal 11 degree target crown, this arrangement is not only very accurate but very comfortable to shoot even with max loads with 200 to 225 gr. bullets.  .358 Bellm loves 225gr. Nosler Ballistic Tips and H-322 powder.

6.8 SPC New Custom Barrel, 20 1/2" stainless steel, set up for both rimmed and rimless ammo.  Use 6.8 SPC CASES MADE FROM MORE READILY AVAILABLE, CHEAPER .30/30 BRASS!


Rimmed or rimless, have it your way.


6.8 SPC is an interesting little cartridge, easily made from .30/30 brass in the event you also prefer rimmed cases in the TC guns.

  Cutting a rim counterbore in the end of the barrel is all that is required!  

No change to the chamber is necessary; however, the chamber can be deepened to the equivalent of a .270x 7-30 Waters, roughly speaking, and still use the standard 6.8 SPC dies, then size the web of the case with a body die, which I can also supply (same as the .375 Super Mag size die). 

.17 Rem. Fireball/.17 Mach IV G2/Contender. This is an excellent conversion.


.17 HMR 14" G2/Contender barrel rechambered to .17 Remington Fireball, same as the old original wildcat .17 Mach IV.  As with all cartridge barrels, the throat is the key, and my throating of the .17s has always produced excellent accuracy.  

 It is the precision throat alignment, minimum throat diameter, long leade angle, and sufficient cylindrical section of the throat that makes this barrel a steal!  Remington factory ammo and brass have been available.

 In the event you cannot find either, I can custom form brass from .221 Rem. Fireball brass.  Dies have been readily available at non-custom prices. 

.357 Rem. Max 10 inch stainless.  Any barrel cut to 18" or shorter, with the possible exception of the tapered Super 16 barrels, can also be relined to the smaller chambers and bore sizes, .35 cal. and smaller. 


This was a TC factory .223 Rem. barrel that I had rebored to .357 and then I rechambered it to .357 Rem. Max. Precision recrowning is part and parcel of rebore conversions. When starting from a smaller chamber,

 I have the option of cutting closer chamber tolerances and of course there is no factory forcing cone as is the case when starting from a stock .357 Mag. factory barrel. The entire chamber and throat are all my work. 

I have not started grading those jobs that turn out particularly well, but this one would sure make "Mike's Pick."  Externally this used barrel is excellent. From a machining standpoint, it is "top drawer." This barrel makes a super deer handgun! 

.357 Rem. Max. 12 1/2 in. "blued" with my muzzle brake machined in and baked Teflon finish.


This was a 6mm TCU factory barrel someone had ported directly into the rifling.

 I cut off the excess, had it cut-rifle rebored with a 1-15" twist, then rechambered it to .357 Max. and worked around the original porting machining in my brake, thus the somewhat increased spacing between ports.

 Drilled and tapped with original TC 4-screw pattern for scope base.  

 Baked teflon finish by Jim Hendershot, SHOTS Gunsmithing near us here in Oregon.  An outstanding deer harvesting machine!  

 Note: In the process of relining a barrel that has a brake machined in or permanently attached, I can work around the brake and retain it.

Close up of ports in the .357 Max. 12 in. barrel above


Ports are spaced farther apart than in the brake pictured below.

 Has my lathe bored expansion chamber inside and 11 degree precision crown tucked down inside behind the last ports

Close up of brake

.444 Marlin S-14 blued factory TC production barrel I rechambered and machined my brake into, then added the 6-screw Weaver scope base. 


There has always been a lot of noise made about exotic, mystically powerful "hand cannon" rounds for the Contender requiring custom dies.  Facts are facts. The .444 Marlin's chamber diameter lets it run at higher pressure than the .45/70, and its bore size combined with the higher pressure gives you ABSOLUTELY all the energy you can squeeze out of a Contender safely.  Physics is physics, facts are facts..... 

anything else is bs.  Common dies, factory ammo, and a plethora of excellent .44 cal. bullets, both jacketed and cast up to 300 gr. or more make the .444 Marlin the ultimate Contender/G2 sledge hammer with excellent accuracy even from factory ammo.

 It normally groups around 1" with factory ammo.  In the hands of a decent handgunner, it is fully 200 yard capable, and my brake, or even the TC factory Muzzle Tamer brake, makes .444 Marlin very manageable. Without a brake, it is brutal to shoot, in my opinion, though some stalwarts with a high pain threshold do shoot it without a brake.  I have shot numerous .444 Marlin factory braked barrels without the weight of a scope to reduce recoil sighting in open sights. 

There is no doubt you unleashed some horsepower, but it does not reach the level of painful, and there is not much muzzle rise, twisting, or stinging sensation.  As you will note in the pix, my brake gives you more ports than TC's brake and more force downward on the muzzle to minimize muzzle rise.  If you really need all the juice you can squeeze from the Contender, .444 Marlin is it, and it is the most expedient, easiest to work with along the same "user friendly" lines of the .357 Rem. Max. 

 For Inquiries 


Mike Bellm  541.956.6938  

[email protected]

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