MAG primers in 45 Colt?

[fordson]

I'm planning on loading up some light 45 Colt loads for use in my Uberti 1858 REM Carbine using a 45LC conversion cylinder. I'll be loading 250 grain LRNFP bullets and either BULLSEYE, IMR4227 or maybe TiteGroup at the starting load range. I've lots of loading manuals, so I'm good for data. However, the manuals show LP primers but not MAG LP primers, which is what I have. I'm of the opinion that at the lower, starting range, the Mag primers shouldn't be an issue. But I'd like the group's opinion and thoughts, if for nothing else than to start a discussion on mag primers, once again.
Thanks

 

[mikld]

Much discussed topic in today's reloading world. You'll get several good answers. I just begin a load work up with starting loads when I have to substitute any component. Technical answers and maybe some formula will follow but magnum primers are safe to use in most standard applications and performance info will come from testing your loads in your guns...

Magnum primers in standard primer applications at DuckDuckGo

 

[rockquarry]

What you're doing would be fine. I have compared many handgun groups fired with standard and magnum primers. In my situation, that usually means CCI-500s vs. CCI-550s or CCI-300s vs. CCI-350s, but I've used other standard and magnum primers on occasion. These have always been American-made primers; never used foreign primers but I would guess results would be similar.

Most of the time, any difference in velocity or group size is so small as to be insignificant. If I find one primer provides measurably better accuracy than another, I'll probably stick with that one. It's best to do testing using a good benchrest setup and shoot groups at 25 yards. Shooting closer is a waste of time and components. Shoot lots of groups and don't let ES and SD numbers get in the way of developing an accurate load. Good luck-

 

[DWalt]

The principal difference between regular and Magnum primers is that the Magnum primer cups are a bit thicker to better withstand higher pressures. Ballistically, there is little difference in performance.

 

[Funflyer]

I've compared mag vs standard primers in 9mm and concluded mag primers are good for about 30fps or 2 tenths of a grain of powder depending on burn rate.

 

[stansdds]

Since you are beginning with the starting load, the use of magnum primers will not be any sort of issue so long as your revolver does not have a light hammer strike. Magnum primers usually need a pretty good whack to ignite, revolvers with reduced power hammer springs or shortened tension screws might cause light strikes and failures to ignite.

 

[chief38]

10 years ago I would have said absolutely not - but the more I read and learn, I see there is little significant difference. I guess the Primer shortages and prices have prodded reloaders into using what they have on hand. While I have never used magnum primers for standard loads I have used standard primers for magnum loads. The result was 30 - 40 fps lower velocity on average. As long as one loads to the max, I doubt what you are asking would cause any harm.

 

[358156hp]

Look at the powder manufacturers loading data for your caliber to get the correct information on which primers to use. The powder manufacturer determines the correct primer, not the marking on the headstamp. Example: H110/296 in 44 magnum requires magnum primers because the powder requires magnum primers for proper ignition. 231/HP30/Bullseye or whatever require standard primers because those powders don't need a magnum primer for proper ignition. Case size is meaningless, H110/296 would require a magnum primer regardless of caliber, plus proper loading density.

Read the manuals.

 

[alwslate]

Look at the powder manufacturers loading data for your caliber to get the correct information on which primers to use. The powder manufacturer determines the correct primer, not the marking on the headstamp. Example: H110/296 in 44 magnum requires magnum primers because the powder requires magnum primers for proper ignition. 231/HP30/Bullseye or whatever require standard primers because those powders don't need a magnum primer for proper ignition. Case size is meaningless, H110/296 would require a magnum primer regardless of caliber, plus proper loading density.

Read the manuals.

A slight correction is needed here. "231/HP38, Bullseye or whatever" do not "require standard primers". Standard primers are often used in the load data however because magnum primers are not required. Magnum primers work just fine with small charges of fast burning powder and improve consistency with very little effect on velocity

 

[Cdog]

I've used magnum primers in standard pressure loads without issue.

I try to steer far away from higher pressure loads in non Ruger .45 Colt applications.

 

[mikld]

i believe the main reason for magnum primers is to reliably ignite slow burning powders or harder to ignite powders. I've read harder cups on Magnum primers is because of a need for higher chamber pressure containment. Some reloaders have found their use of Magnum primers with their loads in their guns produce more consistent Standard Deviations and can improve accuracy. But as a newer reloader, go ahead and substitute your Magnum primers for standard primers and do a new load work up beginning with manuals' listed starting loads...

 

[Rpg]

The only experience I've had using magnum primers vs standard was working up a load for 350 Remington Magnum.

I found two loads listed that differed only in that one called for magnum large rifle primers and the other standard large rifle primers. So I loaded 10 of each and headed to the range.

The only difference I found was that the magnum primers displayed flattened primers and cratered primers. The standard primers displayed no overpressure signs. I ended up using the standard primers.

These loads were not light loads. They are used with elk.

 

[DWalt]

Most reports indicate little to no performance differences exist between LPPs and LPMPs in identical loads. There is probably a greater difference among different brands of the same primer type than there is between LP and LPM primers of the same brand. Also, note that the Winchester brand makes no distinction between Standard and Magnum pistol primers. And that is what the Winchester box says. Far too much is made of largely imagined differences between regular and Magnum primers, also, in the case of small primers, differences between SP, SPM, and SR primers. All work fine so long as your handgun will fire them all reliably. Some handguns will not ignite SR and SPM primers reliably, and they should not be used. Of course, SPPsand LPPs should never be used in high pressure rifle loads

I am sure this same nonsense attempt at making primer performance distinctions will continue for as long as there are primers.

Personally, I normally consider SPPs and SRPs as being completely interchangeable, so long as the primer is 100% reliable in the gun. It seems to make absolutely no performance difference regardless of load or powder type. I would throw SPMPs into the mix, except that they are essentially identical to SRPs.

 

[Eddietruett]

I've used magnum primers almost exclusively in all my handgun loads for at least 5-6 years. I have a friend who has pressure testing equipment and he ran some test on 9mm for me. Since 9mm is a small case and has a reputation for pressures growing rapidly, that was the cartridge chosen. Using Federal primers and mixed cases, min and max loads were tested using Bullseye, Universal, 231 and CFE Pistol. No appreciable differences were noted with either primer with velocities or pressures. Strangely there were a few loads that gave a little higher velocity with standard over magnum, but IIRC none of the loads varied more than 25-30fps. I also find it interesting that all of the Winchester primers I have on hand say for standard and magnum loads.

 

[6GUNSONLY]

From conventional reloading wisdom, the Magnum orders would make a lot more sense with 4227 than either of the other two powders you mentioned. In reality you are fine with Magnum primers and any of the three powders. In this age of primer prices and shortage, the rule of the day is "use what you have."

 

[ArchAngelCD]

Since you are beginning with the starting load, the use of magnum primers will not be any sort of issue so long as your revolver does not have a light hammer strike. Magnum primers usually need a pretty good whack to ignite, revolvers with reduced power hammer springs or shortened tension screws might cause light strikes and failures to ignite.

I hate to disagree but both the LPP and LPM primers have a cup thickness of .020" so there will be no failures to fire if the gun is in good operating condition. LRP on the other hand have a primer cup thickness of .027".

 

[Paul105]

Some data points that might be of interest

These were the same 45 colt load (same day)
305gr w/h110 (specific load not given)
Freedom Arms 4 1/4" M97

CCI 350 (Mag) 1,157
Fed 155 M Matc 1,129
WLP 1,120
Fed 150 Std 1,120

CCI350 has, for the most part, given highest velocity with H110 in my experience.

Paul

 

[fordson]

Thanks all for your inputs. I figured I was ok, especially as I plan to load at the low, starting end of the listed ranges. About 900fps would be my top end load. Strictly fun target loads. Thanks again…….

 

[ArchAngelCD]

Thanks all for your inputs. I figured I was ok, especially as I plan to load at the low, starting end of the listed ranges. About 900fps would be my top end load. Strictly fun target loads. Thanks again…….

Good luck and have fun. Just a note, a 250gr bullet in a 45 Colt @900fps is more than a fun target load lol. That is a serious load IMO.

Don't go by the velocities reported in the load manuals, they are often inflated. 750fps will be much more fun and easy on the gun and shooter too...

Don't forget the range report, thanks.

 

[jdlii]

I still have Winchester LP primers that have printed on the sleeve that they are good for standard or magnum loads.