.45 Colt and Unique


June 19, 2010, 09:35 AM
I've read many high praises of a 250 to 255 gr cast bullet over 8.5 grains of Unique as being an accurate and mild load for .45 Colt. This reportedly should give me somewhere between 725-800 FPS depending on barrel length.

Now that I've started loading .45 Colt, I would like to work on loading some Unique (I have access to a ton of the stuff). However, I am having a hard time finding actual pressure data for Unique in .45 Colt. I've already been to Alliant's website. They list some loads in .45 Colt, but they don't appear to list approximate PSI measurements. Could someone direct me to some data, or perhaps break out their reloading manuals and list some data for me?

For now, I think I'll be playing with 5.5 to 6.0 grains of 700X under a 200 gr RNFP. Should make a pretty suitable plinker.

Thanks guys.

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June 19, 2010, 10:22 AM
I would suggest picking up a "Loadbook" in 45 Colt for $7. Since the standard 45 Colt is not a high pressure round and traditionally operates @ less than SAMMI max I believe pressures are omitted from most loading data for this cartridge. Also in most load development, the pressures are measured until max pressure is achieved and thus max charge is listed. Velocity and pressure go hand in hand with given boolit weights, if you are reaching a certain velocity the load is developing that said pressure. John Linebaugh's site discuses this in detail. Check here http://www.handloads.com/loaddata/default.asp for loads and some pressures. I think that charge of 8.5gr. Unique has proven to give more like 900fps. in most revolvers using lead boolit's.

Steve C
June 19, 2010, 11:26 AM
Use published data. The Speer #13 lists 8.5grs of Unique as the maximum load for 255gr RCBS cast and 8.6grs as the start load (9.5gr max) for their 250gr swagged bullet. Velocities from their 6" S&W 25-5 test revolver list at 846 fps and 891 fps respectively.

These loads will not exceed SAAMI maximum pressure according to Speer.

June 19, 2010, 11:31 AM
CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.

had good results using LEE Dipper 1.3 (for me, 11.5 grains of Unique) and the Sierra 185 grain JHP. I seat the bullet slightly into the case and roll crimp over the nose.

My 250 grain JHP and 255 grain LFN loads using Unique have been only so-so. If I tip my Blackhawk up before each shot, the groups are better. Sometimes I shoot a +P load using 9.2 grains of Unique (LEE Dipper 1.0) with the Hornady 250 grain and various cast 255 grain bullets. However, these exceed the standard pressure for 45 Colt. Please only use a load like this in a Blackhawk or other over-built revolver.

I take back what I said about Unique being so-so. Sunday I tested 255 gr LFN bullets with 6.8 grains of Unique (and also using 6.2 grains of Titegroup). Five rounds tiping the barrel upward before each shot, marking the holes on the paper, five more rounds tipping the barrel downward before each shot.

I found no significant difference between the center to center distances (1.4" at 25 yards) irregardless of the orientation of the powder in the case. Perhaps there were minor velocity differences, but I don't really care. I also noticed similar performance using 6.2 grains Titegroup instead of Unique.

Both of these loads (6.8 grains of Unique, and 6.2 grains of Titegroup) were within the standard operating pressure for 45 Colt.

June 19, 2010, 11:47 AM
According the the speer manual I have, the max working pressure for the 45 colt is 15,900.

My hodgdon manual shows the following in 250 gr bullets.

unique 7.0 at 11,800 cup to 8.0 at 14,900 cup

listed velocities for the these 2 loads are 720 fps and 788 fps with 7 in barrel.

Hope this helps.

June 19, 2010, 11:51 AM
Later update.....

For the 200 grn bullet they list following

unique 8.0 838 fps 11,600 cup to 9.0 883 fps 14,400.

these also from hodgdon manual.

These loads are NOT considered the higher pressure loads and should be safe in most if not all guns.

June 19, 2010, 11:53 AM
Your Hodgdon manual has data for Unique??

Now, that's pretty strange right there!
Hodgdon has never ever had anything to do with Hercules, and later Alliant Unique powder.


June 19, 2010, 12:47 PM
Thanks sig220mw, that's the kind of information I was hoping for. I should also ask, is that data for cast bullets or jacketed?

If anyone else has data to confirm the kind of CUP pressures that sig220mw is reading, please speak up.

June 19, 2010, 01:37 PM
Again, Hodgdon does not list Unique data, and to my knowledge, never did.
They have never sold Unique, or published tested loads for it in their manuals.

2002 Alliant Powder Guide (who makes Unique) lists .45 Colt / Unique loads as follows.
200 grain JHP - 9.0 = 895 FPS - 11,600 PSI.
250 Lead - 8.0 = 850 FPS - 11,800 PSI
300 XTP HP - 6.8 - 690 - 12,600 PSI.

I would say that the 8.5 or 9.0 Unique / 250 Keith SWC load has been used in new & old Colt SAA's since I was a boy 60 years ago. It is the "standard .45 Colt load" for many people, including me.

It is outside todays SAAMI pressure spec, which is artificially low in deference to a lot of 100 year old guns still in service.
But it is perfectly fine & perfectly safe in any .45 Colt revolver of modern manufacture.


June 19, 2010, 03:38 PM
To show the need for load development for any cartridge. Speer #11 lists 8.5gr. Unique (Hercules) max. with 250gr. swagged SWC for 898fps. Not exceeding 15,900 CUP for all those old Colt SAA's in use out there. Linebaugh has tested Unique with 260gr. cast boolit's for use in Ruger Blackhawk's from 10.5gr./1050fps.@ 24,800 CUP through 12gr./1199fps.@ 30,000 CUP.

June 20, 2010, 01:13 PM
Thanks guys.

Jesse Heywood
June 20, 2010, 05:24 PM
250 Lead - 8.0 = 850 FPS - 11,800 PSI

Lee shows that as a factory load.

June 20, 2010, 06:03 PM
40 Grains 3F Black Powder...250 Grain RNL...7-1/2 inch Barrel...1000 FPS more or less...and a nice, easy, friendly no-strain pressure.

Although 35 Grains ( compressed ) was about all I could get into a Case, where, I was getting 900-ish FPS out of a 'Uberti' Bisley Model...230 Grain Lead Wadcutter Bullet

'777', enough to equal the room taken up by 30 Grains of 3f BP ( but with no compression ) I was right onto the 1000 mark for FPS...same Bullet.

I got 850-ish FPS with the same 230 Grain Lead Bullet in my .45 Snubby, 2-1/4 Inch Barrel, with 10 Grains of 'Unique', but I scared everyone in reporting a seperated Cartridge Case ( Revolver was made for .45 ACP, but had tapered Cylinder Bores allowing .45 Colt Cartridges to be chambered ) and now I feel shy and sheepish.

Plus my Bullet may have set deeper into the Case than a usual .45 Colt Bullet, being a full wadcutter...which kinda scares me even now that I think about it..!

I do not know if 'Unique' has changed or not, over the years.

But, my old Lyman handbooks called for 10.7 Grains of 'Unique' as max for a 237 Grain Lead Bullet...and credits it with 1000+ for FPS in longer Barrels.

I imagine the present day Loadings are calculated in deference to what are imagined to be the weakest reproduction Revolvers...and hence, may or may not be what the specs would be if the only .45 Colt Revolvers out there were pre-war Colt made SAA and DA ones...or, modern S&W ones also.

S&W dragged their feet for EVER on offering .45 Colt chamberings.

June 25, 2010, 03:48 AM
Sorry rcmodel but you are wrong, my hodgdon manual no. 26 does indeed list loads for the 45 colt with unique powder on pages 719 and 720.

The loads I listed are straight out of the manual. It was a 3rd printing in 1994.

Besides, why would I make up BS about such a thing anyway?

I'm sorry you doubt me brother but I don't lie.

June 25, 2010, 04:06 AM
Tallinar......I called hodgdon a few years back to ask about bullet types since they didn't list any in this manual. A tech told me that all loads listed in this particular manual should be considered as able to be used with a "worst bullet in caliber" scenario. I guess that can mean the lowest grade jacketed bullet and lowest grade lead bullet also. He did not specify it any more than that.

June 25, 2010, 04:12 AM
What happened to the editing feature?

I had a typo in my Post above, and there is no longer any 'edit' button present.

Anyway, meant to say "237 Grain", somehow had put 137...

June 25, 2010, 08:11 AM
Fixed it for ya. The edit feature only works for four (4) days, to keep folk from executing a form of revisionist history after the thread has slipped from public view.

June 25, 2010, 08:45 AM
40 Grains 3F Black Powder...250 Grain RNL...7-1/2 inch Barrel...1000 FPS more or less...and a nice, easy, friendly no-strain pressure.

That's not exactly the case...and pressure isn't the only thing that strains frames.

The original 40 grain loading was dropped to 32 grains, and shortly afterward to 30 grains due to bulged and burst chambers and blown cylinders. Topstraps stretched more readily with the recoil forces produced by those pressures, which led to increased headspace in the wrought iron frames...which led to early failures of the kaboom variety. By reducing the charge, the stretch was minimized, and the chambers didn't bulge.

In a modern gun, 40 grains of black powder wouldn't pose any threat, but the problem would lie in stuffing that much of it into a modern solid head case.

June 25, 2010, 09:33 AM
Lots of info here, some of questionable value. For example, "I seat the bullet slightly into the case and roll crimp over the nose." What? The typos, misspellings, and speculations all contribute to the lack of clarity. I wish I had a Hodgdon manual so I could check what's really in there. On the other hand, I think I'll stick with what I have.

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