Every once in a while I see folks ask this, but, nobody has posted a "side by side" comparison.

Well, I just got my back order in from Cabelas and here are the differences.
[snapped a photo with the smartphone for all to see... 44MAG on the left, 44SPL on the right]

NOTE: You cannot use the 44MAG bullet (#42920) in a 44SPL case as it seats too deep at the crimp. You CAN use the 44SPL bullet (#42921 or #42912) in a 44MAG case provided you have enough cylinder length (works fine with my 629, Rugers, and Taurus revolvers).

First: they weight exactly the same. Sampling 20 of each, less than 1grain difference.

Second: The profiles ARE DIFFERENT. 44SPL is more tapered and 44mag has slightly narrower meplat. But, the bullet diameters are both .429" and I have seen less than 0.0005 difference from any of the ones I have sampled. VERY well made.

Third: Crimp groves are at different lengths. Difference is very obvious and will change the expansion accordingly.

Fourth: (lastly and least) the 44SPL comes in 40ct boxes vs just 20ct for the 44MAG. (that I have seen)

Attached Images

20140102_120207-1.jpg (125.8 KB, 61 views)

Thanks for the informative post!

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Nemo

Speer used to make a 45-70 400 grain bullet with 2 canaleurs (sp)(crimp grooves) so you could choose the OAL you wanted. Ivan

Hornady's 300 grain 44 cal XTP has 2 cannelures which is nice.
Use the one near the front for lever action 444 and the one
behind for single shot and long chamber applications.

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Nemo

I am seeing more options regarding lower pressure solutions with either an alternate grove or a different option & part number.

44SPL and 44MAG versions of the Barnes bullets.
45LC and 454C versions of the Hornday FTX

...etc.

I've not seen too many for 38 vs 357, but, I would not be surprised if they are out there.