12 Slug load Testing

[Adam604]

Hi Folks,

Adam604

I've been doing a bit more research and reloading of 12 gauge slugs:

I've performed a few test loads of a mild load of:

Federal Hull
22.9 grains Unique (2.5cc LEE Scoop)
Federal 12S3 wad (pink)
Hard wad (custom made * see below)
1.3 cc COW ( LEE Scoop)
Lee 7/8 oz Key Drive Slug (~370 grains)

Loaded in a Lee Load ALL 1 press

What I was testing was the performance of different primers on grouping and recoil

The day was pretty wet, raining pretty hard on and off while shooting a bit windy too. All shots were at 50 yards.

I used :

CCI Large Pistol Primer

Popped out primer from a used 209 primer cup and pressed in pistol primer on top of a drilled out shotgun primer to provide a base. I modified a .45 hull to use as 209 style primer holder, to remove and press in primers (I then use a .45 shell holder in my press) and it worked out great.

3 shots

Results: Very slow to light off shell, almost as if I was shooting a flintlock, I could hear the primer go off then a definite pause before the shell fired. Very light recoil, impacted 4 inches low. Horizontal grouping very tight 1/2 inch. Spread Left / Right 6 1/2 inches, mostly because of hold I think.

Remington KleanBore Muzzle Loading Primer

5 shots

Results: Light recoil, impacted at point of aim. Horizontal grouping very tight 1/2 inch. Spread Left / Right 3 1/2 inches, mostly because of hold I think. A couple of fliers, I flinched and was having trouble with my rear sandbag slipping

Winchester W209 Primer:

8 shots

Results: Light recoil, lighter than the Federal 209 primers , impacted 1 1/2 inches above point of aim. Horizontal grouping 2 1/2 inch. Spread Left / Right 3 1/2 inches.




Overall conclusion, lower power primers do seem to provide a more uniform horizontal pattern, which would seem to indicate a more uniform pressure...


The photos,

In the picture with the 3 targets the first one labeled PP is pistol primer.. the labels on the other two should be switched..

Notice I changed the header on two of the pictures.. Shot wrong target.

In the picture with all of the "stuff" you can see my "hard wad" cutter and material 3/4 inch pipe sharpened and heat treated, material, cheap 1/8 inch paneling


I'm going to do more testing with the Muzzle loading primers and let you guys know how it goes.

I'm using a Mossberg 500 with cylinder bore barrel with a Browning Rifled screw in choke.


Shamelessly stolen from the internet....



The one thing that 209 primers do well is ignite shotshells. They do this well because the amount of primer material is relatively large, and relatively surefire with a light firing pin strike. The one thing that shotgun shooters demand is sureness of ignition. They do not need accuracy, as they depend on a pattern of shot to harvest their game or break their clay. Thus, the amount and temperature of flame in a shotshell can be far in excess of that in a rifle or pistol cartridge. This situation has resulted in several problems in muzzleloaders, the worst of which is ‘over-ignition’, a term that describes too much flame and pressure for accuracy or safety.

Rifle shooters long ago noted that the most accurate loads were those that ignited progressively, from the back end. Pressures are lower, burning rates are more consistent, bullet jump is avoided and accuracy is enhanced with lower power primers. I well remember loading 308 Winchester target loads with special cases made for small rifle primers, just to enhance accuracy. Target primers are always loaded with less priming material than hunting loads.

Bullet jump is probably the bigger bugaboo with 209's in muzzleloaders. The common brand 209's are so powerful that they will throw a bullet clear out of the barrel all by themselves. There is no great velocity there, but the fact that they will is evident of their greater power. It seems that this greater power results
in the muzzleloading bullet being shoved ahead by the primer alone, before the conflagration of the powder catches up to it. The shove is naturally going to be quite variable, so the distance up the barrel before powder burn catches up is going to be variable as well. Accuracy problems are understandable.

White long ago recommended the use of the Remington 209-4 primer in its 209 using rifles. This primer was especially made for the 410 shotshell and had about half the power of the ordinary 209 primer. It enhanced accuracy in White rifles, but was hard to find at the ordinary sporting goods store. I had to ship mine in from far away and had to buy 5000 at a time to get them. Remington ceased production of the 209-4 last Spring, but has apparently substituted the 'Kleanbore' line of 209 primers. Other manufacturers have advertised 209's made especially for muzzleloaders, the RWS primer being advertised for at least the last year, but I have yet to see any of them in Sporting Goods stores. Using

the lowest power 209 available is the only thing a shooter can do.

[Adam604]

I made a few changes to correct spelling and correct the title

Adam

[hubel458]

What my testing has shown. Best to use shotgun primers for large diameter
powder charges you have in 20 to 10ga. If results are erratic, and this goes
muzzle loaders also, you go to a slower powder, that gives a proper
progressive burn.A lot of fastershotgun powder charges used
are much larger in diameter than they are long!!!
As you go to slower powder you use more, thus making powder
column longer than it is around, thus increasing progressive
burn from where primer is...........and that is how
you keep good power with uniformity.Ed

[skidd041]

I did some chrono testing today with the following load

7/8 oz lee key drive slug filled with bore butter
fed top gun hull
cheddite 209 primer
CB fed 12s0 wad
23 grains unique
tested at 950 -980 fps

24.7 grains of unique
tested at 1213 fps

the same load with 20 grns of promo/red dot
tested 1141 fps

I then checked an old load I had used before wich was

rem gun club hull
win waa12 wad
cheddite primer
1 oz lee slug
47 grns blue dot
this tested at 1610 fps

just thought I would show my results

these loads all shot real tight groups at 50yrds and at 100 yrds shot within 5 " of each other with the occational flyer 1 out of 7 out by about a foot could have been me thou
these were all shot out of a 870 rem with a mossburg cantilever barrel.

[Adam604]

Skiddo41,

Thanks for the chrono data on that load.

The velocity increase with just 2 grains more of Unique is very interesting. That load had real nice results at 50 yards for me.

The results you are seeing with 49 grains of Blue Dot is great, man that must have a bit of a kick... That velocity is as fast or faster than most factory rounds

Are you using a rifled barrel?


Adam

[35remington]

Adam, trying to find "accuracy differences" when shooting the Lee Drive Key slug by varying proper shotshell primer type is measuring with micrometers while cutting with axes.

Your groups are just not small enough to prove any particular point; rather, they reflect the performance of the projectile/wad combination. I suspect variances in group size with a single load combination (shot repeatedly so the deviation of groups can be seen and the variance noted) overshadow any other comparative differences between the correct shotshell priming types.

You need to find a more accurate slug/wad/velocity combo and concentrate on that first.

I note that the normally used shotshell primers shot the smallest groups, while, for whatever reason, you "alibied" the performance of the weaker primers by claiming a change in holding of the gun. Can't see any reason for your conclusion as to weak primer superiority in pressure consistency, because the groups seemed to be quite scattered and poor (especially the weak pistol primers), and thus difficult to draw any positive conclusion from. Appears, rather, that you made a more solid argument that standard shotshell primers (Win 209) group better. You did prove pistol primers are grossly inadequate with the hangfires, though.

The number of shots in the groups are not the same, either. You can't compare 3 shot to five shot to eight shot groups. Although you imply that the standard Win 209 shotgun primer may be the best choice, better than the pistol primers because its 8 shot group was much smaller than the 3 shot group with the weaker pistol primers. And also smaller than the 5 shot group of the milder Remington muzzleloading shotshell primers.

The characterization of the Remington muzzleloader shotgun primers being "better" is inaccurate as it shows much greater vertical dispersion in its five shot group than the claimed 1/2 inch. Its five shot size is larger than the eight shot Winchester group. You need to remeasure. Doesn't support the milder is more uniform pressure conclusion. If you're going to call two of the shots "fliers" you have shot a five shot group that isn't five shots. So, which is it? Five shots or three shots? Why did you shoot a five shot group, then declare two of the shots "fliers" and then insist on comparing it to an eight shot group with no fliers? For that matter, how can you in any way claim the milder primers shot better? Your statistics just aren't there.

I hope you can see just exactly why your testing is a poor basis to draw the conclusions you've drawn. You need to do a lot more shooting than this, without so many "alibis" to draw the right conclusions. Shoot many groups with each combination before drawing any conclusions whatsoever.

"Left and right" grouping is horizontal. "Horizontal grouping" is horizontal. You should have used "up and down" or the word "vertical" to describe vertical dispersion in there somewhere. Had to reread it a couple of times to see when you said "horizontal" you meant "vertical."

Realistically, depending upon a cobbled together low powered priming arrangement to reliably kick off the charge in cold hunting weather is probably not a good idea to pursue.

As you have discovered.

The projectile and its fit in the barrel probably supercedes any "fidding around" testing of this sort. In the scheme of things, comparatively, it does not matter. Unless you substitute a really weak primer, which you did.

A smoothbore barrel with rifling on the end that the wad/slug essentially crashes into before it can spin is not the right platform to attempt to quantify differences in accuracy of correct shotshell primers. Too many more important variables than this are present.

If it sounds like I'm being critical I am, but hopefully in a helpful way to steer you in a more productive direction in improving slug accuracy, via a more sound testing methodology to lead you to more correct conclusions. Rather than apples and oranges, as here.

I've experience with the Drive Key in 1 ounce size. Your time is better spent on other factors.

[skidd041]

yes i`m using a rifled barrel

[vriell]

My name is Len and new to the Forum.I am in the process of reforming 303 shells for using in my 22/410 savage 24.
Can i use the CCI 209 shotgun primers in the 303 shells if making fit and also with the recommended Powder for the 410 shotgun in South Afrika ( PMP - S265 ,
http://www.dlswc.co.za/Reload/default.asp ) I will appreciate help and advice ) I drilled out a 303 shell and fit a shotgun primer and test it without load and working well.
The reason i am doing this is because i am using x millitary shells that must be drilled out before can be used
Africa Greetings