S&W 986 5 inch, 9 mm

[ptah]

I have purchased a mint 986 five inch 9 mm SW revolver.

 

Since the start I have problems with accuracy. It aint grouping at 25 meters as I would espect. My capabilities are better then these results.

 

I'have read that SW might have used .357 barrels in the 986. (Or bad tolerance) 

 

What is the easyiest way for me to measure this? I don't have soft lead so I can't slug it.

 

Made some 9mm's with a .357 bullet but I'm a littel hesitend  about sending oversized bullets.  

 

 

If I'm correct I need to measure my cilinder throat, forcing cone and my barrel size? 

 

There aren't many competent gunsmiths here, before I go knocking on their doors I want to inform me and educate myself.

 

PS I've tried hot and soft reloads, 115 grs to 140 grains.

Cheap bullets tot expensive...

[pskys2]

Try either .358" lead/coated bullets or .357" jacketed bullets.  The 929 I shot needed .358" bullets.

 

More than likely it will need the larger bullets.

 

Also look at the crown of the barrel, if there are obvious burrs it will need cleaned up.

[Joe4d]

my 686 pro series shot like doo doo when I got it,, Muzzle looked like it was cut with a rusty hacksaw.. Sent it back to  have the crown fixed and its fine now.
FYI  I saw a TON of pro series guns with the same crap QC sitting in gun cabinets about the same era.

[EEH]

1 hour ago, pskys2 said:

Try either .358" lead/coated bullets or .357" jacketed bullets.  The 929 I shot needed .358" bullets.

 

More than likely it will need the larger bullets.

 

Also look at the crown of the barrel, if there are obvious burrs it will need cleaned up.

Does the 358 bullets bulge the 9 mm brass ?

[Toolguy]

I just recut the crown and forcing cone as a matter of course whenever I get a new or used revo. They are almost always off from a little to a lot. A choked barrel will kill accuracy also, because it swages the bullet smaller just ahead of the cylinder, then it's not tightly controlled the rest of the way out the barrel. If you tend to these items and use .358 bullets, you will probably get match grade accuracy.

[ysrracer]

31 minutes ago, EEH said:

Does the 358 bullets bulge the 9 mm brass ?

 

No, not enough to mater. I shoot .358 bullets in all my 9mm's.

 

No issues.

[ptah]

9 hours ago, Joe4d said:

my 686 pro series shot like doo doo when I got it,, Muzzle looked like it was cut with a rusty hacksaw.. Sent it back to  have the crown fixed and its fine now.
FYI  I saw a TON of pro series guns with the same crap QC sitting in gun cabinets about the same era.

Had this done by a local gunsmith. I live in Europe sending a gun back is impossible  

8 hours ago, EEH said:

Does the 358 bullets bulge the 9 mm brass ?

A little bit, If you know its there you can spot it.

 

8 hours ago, Toolguy said:

I just recut the crown and forcing cone as a matter of course whenever I get a new or used revo. They are almost always off from a little to a lot. A choked barrel will kill accuracy also, because it swages the bullet smaller just ahead of the cylinder, then it's not tightly controlled the rest of the way out the barrel. If you tend to these items and use .358 bullets, you will probably get match grade accuracy.

Thanks for the advice.

10 hours ago, pskys2 said:

Try either .358" lead/coated bullets or .357" jacketed bullets.  The 929 I shot needed .358" bullets.

 

More than likely it will need the larger bullets.

 

Also look at the crown of the barrel, if there are obvious burrs it will need cleaned up.

I have some copperplated lead bullets from H&N .358, would they suffice? 

[Joe4d]

You can try but dont blame the gun if the accuracy isnt good. I have never got decent accuracy from copperplated.. Although it has been a long long time since I tried them and people seem to like them just fine these days so maybe mfg's figured out better QC... Mike a handful and see if the size is consistent.

 

[ysrracer]

9 hours ago, ptah said:

I have some copperplated lead bullets from H&N .358, would they suffice?

 

Those will be fine.

[pskys2]

10 hours ago, ptah said:

Had this done by a local gunsmith. I live in Europe sending a gun back is impossible  

A little bit, If you know its there you can spot it.

 

Thanks for the advice.

I have some copperplated lead bullets from H&N .358, would they suffice? 

Yes.

[pskys2]

19 hours ago, EEH said:

Does the 358 bullets bulge the 9 mm brass ?

If loaded long enough it shouldn't.  I think 1.170" or longer, if I remember correctly.

[Toolguy]

I could never get any decent groups out of copper plated bullets. The same guns will shoot tight groups with cast and lubed lead, polymer or powder coated, or jacketed bullets. 

[pskys2]

3 hours ago, Toolguy said:

I could never get any decent groups out of copper plated bullets. The same guns will shoot tight groups with cast and lubed lead, polymer or powder coated, or jacketed bullets. 

I've never had good luck with Plated either.

 

But if it's the bullet diameter you should see the groups tighten up with .358" of any kind.  May not be 1" at 25 yards, but it will tighten up from .356" bullets.

[ptah]

Thanks will post a follow up.