Deep Seating Cast Bullets

[44MAG#1]

Does anyone use the deep seating method of loading SWC cast bullets? Such as seating with the front edge of the front drive band seated around .030" below the case mouth and crimped?
With appropriate powder charges?
Interested in the responses of the ones that have experimented with it.
I am interested in doing it in 44 Magnum.

[Outpost75]

I have done it in .357 to load for S&W Model 28 Highway Patrolman which has a shorter cylinder.

When deep seating I would reduce max. charges at least 5%.

Accuracy may not be as good because Keith bullets use the full-diameter front driving band north of the crimp groove to center the round in the chamber and to guide the bullet in its transition from case into the ball seat. When the shoulder is seated inside the case mouth you defeat that function and modern dies tends to size cases too much so that the rounds flop down into the chambers at 6:00, causing mis-alignment of the bullet relative to the throats.

[reddog81]

It certainly can be done, but like Outpost mentions this will generally result in swaging the bullet down in diameter. Leaving as much of the bullet outside the case keeps the bullet at full diameter which is critical for getting top accuracy. On top of that any load data you are using is based on the assumption of normal loading practices.

What are you trying to accomplish?

[onelight]

I have loaded keith crimped over the front driving band and at my skill/shooting level can't tell much practical difference , may not be ideal but works for me.

[44MAG#1]

I am trying something different. That is the only reason. So far I have gotten good results. So just based off that I don't see anything wrong with doing it.
Just asking if someone has tried it enough to give good advice is all.

[Paul105]

I've done it for well over a decade. Started with Freedom Arms 4 1/4" M97 .45 Colt - short cyl (1.610 OAL max). Settled on two loads RCBS 270 SAA (280gr + actual) and 7.8gr of HP38 -- ran about 900 fps and 300gr RCBS SWCGC (320 lubed/checked) 21.5gr H110 CCI350 -- chronoed right at 1,150 fps depending on powder lot and temp. Both loads seated/crimped above front drive band.

Also use the deep seat method in the .44 mag. 6.5 gr HP38 and any commercial 240gr CSWCBB or 429421 or 429244. Gives about 880 fps from 4 1/4" M69.

My favorite is the 429244 SWCGC over 17.5gr A2400 seated and crimped over front drive band (OAL from two diff bullet sources - 1.565 & 1.572"). This load chronos right at 1,100 fps from 2 3/4" M69, 1,150 fps from 4 1/4" M69 and +- 1,200 fps from longer barrels. It's one of the most consistently accurate loads in all guns that I've tried it in. Basically the old Keith load.

Have limited experience with 300gr Hammer from Missouri Bullet Works and 20.0gr H110 seated and crimped over front drive band. The one gun/gun I tried it in didn't care for the combo -- needs more work just haven't got to it.

Also deep seated RCBS 400gr SWC in FA .475 Linebaugh with satisfactory results.
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4 1/4" FA97, 50 yds rested, 270 SAA 7.8gr HP38
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https://photos.imageevent.com/paul105/hobby/large/RIMG0950.JPG
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429244, 17.5gr A2400, 25yds rested on range bag, 2 3/4" M69
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https://photos.imageevent.com/paul105/hobby/large/1a%202.75%20M69-2_%20265%20SWCGC%2017.5%202400%20IMG_1189.jpg
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Some of the better groups but representative of what might be expected from deep seating.
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Lots of good info on deep seating by David Bradshaw on Single Actions website - if interested, I'll try to run down the link.
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**** CAUTION - DO NOT SEEP SEAT WHEN USING STANDARD .44 MAGNUM LOAD DATA -- REDUCED POWDER CAPACITY WILL CAUSE PRESSURE TO INCREASE SUBSTANTIALLY. POWDER CHARGES NEED TO BE REDUCED! SAME CAUTION APPLIES TO OTHER CARTRIDGES!******




Paul

[Bill*B]

Not to be a nag, but if you are using published loads, do pay attention to the COL. I ruined a fine S&W by flush seating a wadcutter over a rather mild load which was intended for a bullet "seated out" a third of an inch or so. I just failed to notice that little detail! Pressure was high enough to spring the pistols yoke. Now, you asked about 0.030", and I doubt that would get you into trouble - but 0.300" sure can!

[ddixie884]

If you deep seat SWCs in .44mag it would have a case volume close to .44spl. you could probably use .44spl load data.

[ABJ]

Bill*B makes a good point. The only time I do it is when the OAL needs to be shorter, then I adjust the powder charge accordingly. My normal is if it has a crimp groove I use it. If I'm not getting the accuracy I want I then move the powder charge around and if I get close then start tightening the crimps. If none of that works I change powders. A perfect example is HP-38. All my 38's and 357 guns love it but one. That one gun hates it but loves Bullseye and Unique in the same velocity range as the HP-38. Go figure!
Tony

[Larry Gibson]

It's not the OAL you should pay attention to but the seating depth. That's what Bill*B is actually referring to.

[Paul105]

Added the following to my original post above.

**** CAUTION - DO NOT SEEP SEAT WHEN USING STANDARD .44 MAGNUM LOAD DATA -- REDUCED POWDER CAPACITY WILL CAUSE PRESSURE TO INCREASE SUBSTANTIALLY. POWDER CHARGES NEED TO BE REDUCED! SAME CAUTION APPLIES TO OTHER CARTRIDGES!******

Paul