New Ruger PC Carbine with some test data

[winelover]

Mediocre accuracy, could be the nature of the beast. Don't have a Ruger but I have sent over 5K rounds down my backyard range through my CZ Scorpion carbine and after market trigger. Four different cast bullet deigns and at least a dozen different 9 mm friendly powders. All 10 shot groups from 60 yards, sitting with a tripod for a front rest. Red dot sight or a 4 power scope...............doesn't matter. I'm happy if I can manage just under 2 MOA. I have shot one ragged hole, many times but with only fifty percent of the shots.

When I find a combination that works, I will load fifty rounds, shooting ten per day.............varying temperature conditions. Only after confirming repeatability, will I load in bulk. As little as two tenths of a grain of powder will make or break a load in that small shell casing.

Winelover

[FergusonTO35]

Well, looks like things are not working out. Perfect weather yesterday with little wind and mild temperatures. At 50 yards my reloads with the Lee 358-125-RF, which shoot great in all my handguns, were absolutely terrible. Some rounds aimed at one 16x16 target would strike the other one next to it!

Went back inside and cleaned the bore really good, found zero leading or other issues. Went back out and put 5 rounds each of three different types of factory rounds through it as a baseline. Accuracy improved to roughly minute of bad guy with 4" groups but nothing more. At 50 yards with quality factory ammo I don't think a 2" group is too much to ask for. So, back to Ruger it goes. They sent me a shipping label so hopefully it will come back fixed soon. I have read that some of these carbines have needed new barrels.

[Burnt Fingers]

Well, looks like things are not working out. Perfect weather yesterday with little wind and mild temperatures. At 50 yards my reloads with the Lee 358-125-RF, which shoot great in all my handguns, were absolutely terrible. Some rounds aimed at one 16x16 target would strike the other one next to it!

Went back inside and cleaned the bore really good, found zero leading or other issues. Went back out and put 5 rounds each of three different types of factory rounds through it as a baseline. Accuracy improved to roughly minute of bad guy with 4" groups but nothing more. At 50 yards with quality factory ammo I don't think a 2" group is too much to ask for. So, back to Ruger it goes. They sent me a shipping label so hopefully it will come back fixed soon. I have read that some of these carbines have needed new barrels.

It's not your carbine.

I've yet to find ANY 9mm carbine that will do 2" at 50 yards.

I can shoot one hole groups at 25 with my Ruger PCC, PSA AR9, and Ruger PC Charger. Go out to 50 yards and the groups open up by a factor of at least 3.

My theory is that those short fat bullets when going transonic lose stability. However.....I've shot subsonic loads and had the same problem.

I've tried bullet weights from 115 gr to 160 gr, J-word and cast. I've used over a dozen different powders. I've shot at least a dozen different factory loads.

None of them will do 2" at 50 yards. There are over two dozen 9mm carbines in my group of shooting buddies. We've all been chasing this for a couple of years.

We've come close. We've shot a few 2.2 groups. But those are three shot groups. I prefer a minimum of 5 and really lean towards 10.

[tazman]

I had one of the 9mm carbine imports that was built like a M1 carbine. It would hold 2 inch groups at 50 yards but only with 147 grain cast boolits.
115 grain and 120-125 grain boolits, not so much.
The trigger was awful and the sights fell off after a few dozen shots so I didn't keep it.

I had hopes for the Ruger PC carbine but it sounds like it isn't going to be a good rifle.

[FergusonTO35]

Thanks guys. I guess if it doesnt work out Ill see about selling or trading into another .357 lever action. Life is too short for inaccurate rifles!

[winelover]

This is one of the very first groups, shot with a 9 mm CZ Scorpion carbine. Seated at 60 yards off a tripod. Using a Trijicon reflex site with a triangle reticle. Triangle depicts the POA. That bullseye is 3" in diameter. At least five of the 10 shots are in one hole. Near impossible to get all one hole, at least for me.

That load is a +P load and only safe in my firearms at my particular seating depth. Should be worked up, gradually.

Winelover

[Bigslug]

I'll likely be joining you guys on this saga ere long, but maybe some perspective is in order:

Les Baer will guarantee 1 1/2 to 3" groups at 50 yards depending on the specific model of their 1911 under discussion. This is with a ~$3,000 hand-built, locked-breech gun that would probably require you to bring a mallet in order to pound a hydrogen atom in between the slide and frame rails. This is shooting the notoriously non-finicky, low-pressure, pretty much always subsonic .45 ACP.

Blowback, take-down action, "reliability first" tolerances, and a cartridge inherently lacking attributes that would make it easy to load accurate ammo for, that in its most common formats, will be going transsonic not far past pistol-fighting distance. Pretty sure Georg Luger would have been tickled with 4" 50 yard groups.

Given the fast 1-10" twist, long 147 grain hollowpoints at about 950 fps would seem the ideal place to begin..

[FergusonTO35]

My thing is, the Lee 358-125-RF is always accurate at 50 yards from my Marlin 1894 regardless of what load I'm using. Not sure why it would be any different out of a 9mm carbine. In fact, 4" groups are what I was getting with factory FMJ ammo. With boolits, at least 50% of the rounds were fliers that went way off course. This tells me there is likely something wrong with the bore.

[Burnt Fingers]

My thing is, the Lee 358-125-RF is always accurate at 50 yards from my Marlin 1894 regardless of what load I'm using. Not sure why it would be any different out of a 9mm carbine. In fact, 4" groups are what I was getting with factory FMJ ammo. With boolits, at least 50% of the rounds were fliers that went way off course. This tells me there is likely something wrong with the bore.

Different rifle, different cartridge.

See the post by Bigslug.

Did/do have the takedown nut correctly tensioned?

What you're doing comparing one rifle using a boolit to another rifle and cartridge using the same boolit is like asking why the gas in your Pinto doesn't run like the gas in your Corvette. It's the same gas so the two platforms should run the same...right?

50% of boolits are flyers? Are you getting any leading?? Have you actually checked for any leading?? Is the takedown system properly set up? What size boolits are you using? Have you tried a fatter boolit?

9mm isn't known for being the most accurate round out there to start with.

Myself, I think you're expecting WAY to much of the cartridge and the carbine.

One thing being missed here is the difference in twist rates. Your 1894 is what??? 1:16? The Ruger is 1:10. The faster twist is going to highlight bad casting technique. Out of round boolits, voids in boolits, and things like that.

If factory ammo is shooting 4" at 50 out of the Ruger and your loads are all over the place I'd suspect your loads before the gun. It's basic common sense.

[Bigslug]

If we were to take this to an insane level. . .

Start with one of the "long" 9mm cases (i.e. .38 Super) and trim it back to near-max headspace for the gun. Then uniform the primer pockets and flash holes. Those steps should work towards making the lock, ignition, and barrel time as consistent as possible

Weigh the cases and segregate to batches within a grain of each other

While it flies in the face of economy/volume plinking with cast projectiles, gas checks would be worth studying as a means of dealing with the tight twist.

[M-Tecs]

If one were going to cut down brass there are other long 9mm cases that have the same .394 head size. The 38 Super is 406".

Haven't shot mine yet with cast. If I can get 3" at 50 yards I will be happy.

[FergusonTO35]

My boolits are sized .358, bore is clean as can be after shooting. Takedown nut is tensioned as per the manual. If this gun doesn't work out, no big deal. Looking forward to seeing the Rugerlin 1894's at some point.

[Burnt Fingers]

How many loads have you tried?

How many boolits?

[FergusonTO35]

I've tried a number of different loads with Bullseye, HP-38, Unique, and Green Dot. Boolits I have tried include the Lee 356-120-TC, 358-125-RF, and Arsenal 359-130-RF. As you know, purchasing a wide variety of powders to try isn't an option these days. Fedex picked it up today for the trip back to Ruger.

[M-Tecs]

I know several people that have S&W 952 or AMU style 92 bullseye 9mm guns. They have expended a great deal of energy to get cast to shoot as well as jacketed at 50 yards in the 9mm. They have not been very successful. The guns shoot great with jacketed and 9 ring with casts. They don't have the same issues with their 45 bullseye guns. With lead they can still shoot High Master scores with lead in 45 ACP. The 9mm and cast tend to be more challenging to get great accuracy.

Did you shoot jacketed in it too establish a bench mark?

[WinchesterM1]

If one were going to cut down brass there are other long 9mm cases that have the same .394 head size. The 38 Super is 406".

Haven't shot mine yet. If I can get 3" at 50 yards I will be happy.

I don’t know if I have the exception or not, but my PC9 with mixed brass and CCI spp with a MP 359-135 RF PCed over 3.8 of bulls eye loaded on a Dillon SDB, with a lucid red dot I can hit my 3” spinner at 100 yards 90% of the time

[M-Tecs]

I don’t know if I have the exception or not, but my PC9 with mixed brass and CCI spp with a MP 359-135 RF PCed over 3.8 of bulls eye loaded on a Dillon SDB, with a lucid red dot I can hit my 3” spinner at 100 yards 90% of the time

I haven't shot mine with cast yet. With jacketed it's mostly been at 25 yards indoor due to weather.

I do have a very good friend that has two that is getting similar results to yours. He is a High Master in NRA Highpower and Long Range but he has taken up pistol caliber carbine competition. He uses them as his comp guns and the only thing he's done is to work on the triggers. He is getting 3 to 4 inch groups at a 100 yards using jacketed bullets with both guns.

When I'm done with load development I could live with 3 inch groups at fifty but the goal is 4 inch at 100. I have seen tricked out AR based 9mm Competition carbines do sub 2 MOA at 100 yards for 10 shot groups but the Ruger is a removable barrel so I am not sure what realistic. Most are reporting sub 2 inch groups at 50 yards.

https://www.americanrifleman.org/art...rity-9-pistol/

https://www.thetruthaboutguns.com/gu...er-pc-carbine/

https://theolddeerhunters.com/ruger-pc9-carbine/

https://www.rugerforum.net/threads/p...-yards.369565/

https://www.rugerforum.net/threads/r...curacy.375753/

[FergusonTO35]

Did you shoot jacketed in it too establish a bench mark?

Yes, with both factory and reloads. The best it will do is a wandering 4" group. If Ruger says this is "normal" then I'm going to move on. No point in having a pistol and carbine that can share ammo, but still have to stock a special load for the carbine just to get mediocre accuracy. All the links above show the PC carbine making much better groups than mine does. The 100 yard group here: https://theolddeerhunters.com/ruger-pc9-carbine/ is what mine will do at 50.

[Hogtamer]

Let me know if you decide to sell it.

[FergusonTO35]

I certainly will!