9mm Convertible Blackhawk

[Zaydok Allen]

I'm looking at a Blackhawk that comes with a 9mm cylinder. Since the bbl must be made for a .357 or 38 special sized bullet (.357), what kind of reduction in accuracy can be expected by swapping cylinders and shooting 9mm? I ask because 9mm bullets are .355 in diameter.

Anyone own one and see a difference in accuracy?

 

[BCRider]

From reading past discussions around here I think you'll find that the Convertable has a barrel which is a little tight for the .357 and a little loose for the 9mm. It's sized in between the two. In one case the bullet simply swages down a little as it passes into the rifling and in the other it hopefully obturates out to seal.

There's some things you can do to aid in better accuracy with the 9mm option if you reload your own ammo. First is to go with lead bullets. Cast lead 9mm bullets tend to come in .356 or sometimes even .357 depending on the supplier. Second is if you prefer jacketed factory ammo look for some where the jacket is open on the rear with the back of the lead slug exposed. The pressure should aid in making the bullet act somewhat like a hollow back wadcutter by swelling the jacket out to form to the barrel bore more tightly. To determine if your ammo uses this style of bullet you may need to use a inertia bullet puller to pop out bullets from a variety of stock factory ammo to find one which uses this style. Hopefully testing for accuracy from a rest confirms what I suspect SHOULD prove to be a more accurate factory loading.

 

[firesky101]

My father has one that we shoot a lot. I have never bothered to put it on paper, but the accuracy has never seemed like a problem. I always seem to be able to hit old oranges at 25-50yds. Come to think of it he has a lot of blackhawks and they are all very accurate, the .30 carbine is my favorite. It makes one heck of a flamethrower.

 

[Zaydok Allen]

Hitting oranges at 50 yards is not bad at all. That was with the 9mm and .357's both? If so, that's plenty accurate for my desires. I'm not a competitive shooter or anything. I just want a full size .357 because I have a SP101 already, but shooting 9mm's would be a nice cheep alternative.

 

[PO2Hammer]

If you want a lot of responses there have been 2 or 3 threads on this in the past few months. Try a search if you want a lot of info.

I had one about ten years ago and mine shot very well. I was getting 3" - 4" groups at 25 yards off hand with the 9mm cylinder, never did bench test it. With .38/.357 it shot a little better.

 

[firesky101]

Yeah 9mm and .357 just need a couple of ranging shots to get the POI down. I love old oranges they roll well so I don't even need to leave the bench, and are pretty reactive.

 

[TarDevil]

I started a similar thread a month or so ago... I was happy enough with the responses to put this gun on my short list.

 

[Zaydok Allen]

Cool. I'll do a search and read up. Thanks guys.

 

[GJgo]

The cheapo Blazer brass 9mm plinking ammo shoots great in mine. More expensive SD ammo doesn't shoot so well. Just have to pick & choose.

 

[TennJed]

I see no noticable difference in mine.

 

[CraigC]

Most folks will say that accuracy does suffer but in 25yrs of studying sixguns and shooting, I have never seen a face to face bench test showing the difference between the two. I think most go by seat of the pants offhand shooting which doesn't really tell me anything useful. I would like to see one sixgun tested, either from the bench or with a Ransom rest, using several different loads from both cylinders.

 

[Zaydok Allen]

I need to get a ransom rest and a chrono. I've always wanted to do some formal testing of my guns to see how they perform under scrutiny.

 

[CraigC]

Me too! I've had the Ransom rest and all the inserts I would need on my wishlist at Midway for a while but just haven't been able to pull the trigger on it, so to speak.

 

[76shuvlinoff]

I recently sold my convertible Blackhawk to fund an SP101 for the wife. I am not skilled but if I could stay on a paper plate at 25 yards with the 9mm cyl (free standing) then I know it shoots better than that in better hands.

 

[SabbathWolf]

Here's mine.




Shoots pretty good with 357 and 9mm both.
But at a distance 9mm will need the sights adjusted.

 

[highlander 5]

If you reload 9mm just use a .357 cast bullet of some type and in the same weight range.
Since it's a revolver bulet shape isn't a concern for reliable feeding. SAAMI spec for 9mm barrels can be as large as .359" and still be considered within specs.

 

[WC145]

In my experience people make way more of the .002" difference than there really is. I have a S&W 360J that started life as a .38spl and has been rechambered to 9x23 and I have seen no appreciable difference in accuracy going from .38s to 9mms. I have no problem qualifying with it or shooting it in IDPA BUG matches.