A Comparison of .30 Caliber Contender Cartridges ..... and the Great Contender Arms Race for highest claimed velocities.

Choosing a high performance.30 cal. Contender cartridge can be confusing with all the hype each promoter has to offer in support of his cartridge.

 There is something of an "arms race" between the promoters of various Contender cartridges.  Each promoter says he is the best, and to some degree each is right.  So let me add my take on the situation

L to R:  .308 Win, .30 Bower Alaskan, .30/30 Win., .308 Bellm, and .309 JDJ

I failed to list the excellent .30/30 Ackley Imp. to the cartridge lineup, as well as Gary Reeder and Bullberry variants of it.  But as we go through comparisons of the cartridges shown here, I think you will see why they are in a different league, and why I would reserve them for either rechambering the old 6-groove S-14 factory .30 Herrett barrels or for new custom barrels.  This is due to the need I see for going to a longer cartridge to cut out the original factory throat.

.308 Win. pictured on the left is for comparison only. 

It is definitely NOT an option in the Contender.  It is a definite frame stretcher.

Starting with the .30 Bower Alaskan, in many respects this is the very best of the .30 cal. Contender far as the cartridge itself goes.  However, a number of things must be taken into account with each cartridge before taking the plunge having a barrel made or rechambered for it.

On the plus side, .30 Bower Alaskan uses the extremely thick, though apparently somewhat softer .307 Win., case which is about half again thicker in the case wall near the web than .308 Win is. This extra thickness is what helps permit the velocity feats of the .30 Alaskan and many other cartridges based on .307 Win brass.  .30 Alaskan also has the admirable 40 degree shoulder, and of course a rim.

It has an excellent "Wow factor" with the velocities reported from it.  However, these velocities are somewhat predicated on a 1-14" twist, which means either rechambering one of the old TC factory 6 groove barrels or going full custom.  And full custom these days is getting saltier all the time for those who are shooting budget conscious.

Maximum loads for .30 Bower Alaskan are determined largely by whether a cartridge will extract or not, which from my experiences over the years indicates the pressures are much higher than should be fired in the Contender with this diameter of cartridge.  Using extraction alone as the upper limit indication is not very prudent, in my opinion,  nor are calculations from the Powley Computer that Don Bower relies on fully applicable to the Contender.  Can you get away with Don's methods?  By and large, yes.  But I do not believe in having shooters gobble up the last margin of safety and stretching things this far in the Contender.

Anything with a non-standard shoulder, such as the 40 degree shoulder made famous by P.O. Ackley and shared by the .30 Alaskan, comes with a custom reloading dies price tag, which is another detraction.

Comparing the lengths of .30/30 Win and .30 Bower Alaskan, you can see they are very similar in length.  In fact, the .30/30 case is slightly longer at 2.039" v. 2.025."  Thus when rechambering for the .30 Alaskan, the throat from the original .30/30 chamber remains, and if it was oversize in diameter from the factory and/or badly misaligned by the factory chambering with a drill press, that portion of the chamber will remain after rechambering. 

TC made the 6 groove 1-14" twist barrels chambered for both .30/30 and .30 Herrett.  While Don says there is no difference in accuracy between the two, I personally would opt for rechambering a .30 Herrett and getting a new throat in the deal instead of having the old .30/30 throat remaining.  Some of the factory throats are very badly misaligned with the bore, and I would hedge my bet on the side of a new throat aligned with the bore if possible.

Capacity of the .30 Alaskan is optimum, in my opinion.  The .308 Win holds more than enough powder to stretch a Contender frame in a heartbeat.  So why add capacity by blowing the shoulder out to 40 degree?  The main reason I see is to make enough capacity for slower powders and thus optimize performance with heavier bullets in the 150 to 165 gr. range.    Also, because of the extremely thick walls of the .307 Win. even though it and the .308 Win are dimensionally the same outside, the .307 Win case has a much reduced powder capacity and can stand more room inside for the slower powders.

One other downside to the .30 Alaskan is the fact that it will fire factory .307 Win. ammo, which is loaded to about the same pressures as .308 Win.  The somewhat greater volume of the  .30 Alaskan chamber drops the pressure of .307 Win ammo shot in it some, but I question whether the reduction is sufficient to make it safe to the frame to do so.  To me, this is definitely a gray area where trouble can develop if factory ammo is fired in it.

.30 Bower Alaskan is a terrific cartridge, so far as the cartridge is concerned when rechambering cuts out the original factory chamber and throat..30/30 Win.  This old standby just lacks the power the potentials the Contender will permit and is here for comparison only.  While excellent accuracy can be had from it in good custom barrels, it has been seriously undermined by the way TC has chambered for it.  Earlier barrels were chambered in a drill press with the chuck holding the reamer rigid so it could not follow the bore and which did not take into account variations in the exterior diameters from one barrel to the next, which I have found to be as much as .007."  This variation in diameter moves the axis of the bore off center and resulted in chambers being stabbed at the barrel instead of aligned with the bore.  Later barrels, primarily 8 groove barrels, had no throat in them at all.  The chamber necks were cut .050"  longer than the case length and the riflings had a chamfer cut on the ends, but this is not a throat.  Accuracy from these barrels is usually mediocre at best.  So if you want a good .30/30, go custom and make sure of the throat diameter and shape before committing to it..308 Bellm.  One of the main reasons for picturing .308 Bellm here is to show its case length in relationship to the  .30/30 and hopefully thereby help in conceptualizing cutting a chamber for it and in the process cutting out what is in front of a .30/30 chamber.  Compare the .308 Bellm to the .308 Win. and you can see the similarities in the cartridge bodies of the two, the .308 Bellm being .040" longer in the body.... that distance from the shoulder to the headstamp.  The main reason for the added length in the body was to prevent a rimless factory .308 Win. round from firing in this chamber.  Instead of firing, it simply drops down into the chamber .040," which should be far enough to keep it from firing.  .307 Win. ammo will fire in the .308 Bellm chamber, but with its greater volume and "blow by" of powder as the bullet passes through  the long chamber neck, pressures should be reduced enough to not be a danger to the frame, though there is no reason to shoot .307s in the .308 Bellm due to the long jump the bullet must make getting to the riflings.

If you compare .308 Bellm data to published .308 Win. data, you will see that max. loads for each are not far apart.  In the process of test firing .308 Bellm chambers, I frequently run loads up pretty close to book maximums for .308 Win.  The added chamber volume appears to drop pressures just enough to keep from sticking cases or stretching the frame.Strength of Brass.  While the .444 Marlin parent brass for .308 Bellm is quite thick near the web and appears to be harder than that of .307 Win brass, it is no where nearly as thick as .307 Win brass.  Yet I cannot find any difference in the way the two cases handle pressures in the Contender.  I have substituted one for the other in shorter chambers and find that both work extremely well in minimizing the amount of force exerted by the case head against the breech face of the frame.  If there is a difference, it is minute.  Both .307 Win. and .444 Marlin brass do an excellent job in the Contender, but favor goes to the longer .444 case which permits cutting out existing .30/30 chamber throats and thereby facilitating improving the accuracy of the end product.

I'll not repeat the advantages of using standard dies for the .308 Bellm, but rather refer you back to the "Triad" page.Capacity.   The .308 Bellm holds enough of the same burning rate powders to do the same thing as both the .30 Alaskan and the .309 JDJ, but as stated in the Triad article, the .308 Bellm has the advantage of maintaining fairly high loading densities with the faster powders used for lighter bullets compared to the .309 JDJ.  Thus, the .308 Bellm is better suited to the full range of bullet weights handgun shooters normally use, namely 125 gr. to 165 gr.

.309 JDJ is an excellent cartridge that in reality was developed for/by Bob Hutton back in the early 60's before the Contender was even brought onto the market.  I do not know for a fact that P.O. Ackley did the original work for Hutton or not, but P.O. describes the case in his Handbook for Shooters and Reloaders, Vol. II, 1966.  It has the charactreristic Ackley body taper with a .455" shoulder diameter and 40 degree shoulder angle that Ackley made famous in custom gun circles long before the copycats rushed in  to stake their claim to fame on Ackley's concepts.

If .308 Win holds more than enough powder to  stretch a frame, the only excuse for a capacity nearly that of a .30/06 is to be able to stuff it full of slow powder behind a heavy bullet, but at the cost of extra muzzle blast and a cartridge that is not as flexible with lighter bullets

And as stated early on, the 40 degree shoulder always comes with an extra cost for custom dies.The Arms Race:  Which one is the fastest?  All are faster with slower twists, for one thing, and the slower 1-14" twist makes the .30 Alaskan stand out.  Unless you believe in metaphysics and alchemy, how can similar burning rate powders in straight walled chambers of the same diameter using strong brass cases fired with the same weights of bullets in the same lengths of barrels produce significantly different velocities?  It takes pressure over time to produce velocity, and other than reducing resistance by using a slower twist rate and narrow rifling (compared to TC's older vintage of ill-conceived equal land and groove rifling), exaggerated velocities have to be accompanied by exaggerated pressures.  Go the higher pressure route in the Contender, and you run a strong risk of stretching the frame if you are lucky, stretching the lower lip on the barrel lug and ruining it if you aren't so lucky.  Talk to enough people and you will turn up quite a few stories about ruined frames, victims of the great Contender Arms Race.

.308 Bellm was originally developed mainly as a rechambering option to resurrect accuracy fromTC factory .30/30 barrels with bad throats , the majority of which are 8 groove with the extremely wide rifling design which tends to run higher pressures than traditional narrow rifling found in nearly all other modern firearms.   Eventually I would like to have data for the .308 Bellm derived from custom barrels to put its published data on par with that of the .309 JDJ so far as rifling type is concerned.  However, it would have to be published with the warning about use in 8 groove barrels, and I am hesitant to have the two sets of data confused with each other.

In the meantime, I have shooters with 8 groove barrels running loads 100 fps or more faster than what I publish and not reporting any problems.  To date, I have had ZERO reports of stretched frames shooting .308 Bellm barrels, including my own shop frames which I deliberately push well past the pressure levels I recommend.Summary:

All of these types of custom rounds belong in a 14" or longer barrel.

1) Starting from a .30 Herrett barrel, rechamber to .30/30 Improved or .30 Alaskan.

2) Starting from a .30/30 barrel, rechamber to .308 Bellm.

3) .309 JDJ and its case capacity do not belong in a Contender barrel, handgun or rifle, in spite of SSK's hype to the contrary, but it makes an EXCELLENT round roughly equivalent to standard .30/06 loads in the Encore when loaded to full acceptable pressures..... ONLY in the Encore.Which one to choose?  I can and do chamber for both .30 Bower Alaskan and .309 JDJ, but do not use the .309 JDJ name when stamping the caliber on the barrel.

Use .308 Win./.307 Win. Improved dies, which is what the .30 Alaskan actually is. Redding makes them, and is the preferred brand.

.30/06 Imp. dies from Redding can be modified for chambers with .309 JDJ dimensions, and I will do the modification at no charge.  It is merely a matter of shortening the die bodies a bit and only takes a few minutes to do.

The choice is yours.

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