Ruger P90DC Problem

[Ronvandyn]

Howdy All!  Need some advice...

I was out at the Bullet Hole yesterday, shooting some reloads I have been building up, and ran across a problem that I have never had with any type of weapon before.

The weapon is a Ruger P90DC 45ACP.  Good gun, never heard any bad things about them, but mine was used when I got it so what may have happened to it before I got it is unknown.  Here is the problem.  I cant seem to get the slide to lock all the way to battery.  Even when manually pulling the slide fully and allowing it to go forward on its own.  Its easy enough to push it into the locked position, but after firing a round it ends up about 3/8th of an inch short of fully closed.  Factory loads also do this, I tried some White Box. 

A friend thinks it might be a weak slide spring and suggests putting a spacer in on the spring guide to see if that fixes the problem.  Personally I have never heard of that being done, but it sounds logical.  Another option of course is to buy a new slide spring for it, which I am seriously considering. 

Suggestions or comments?

Ron

[sjwsti]

Replacing the recoil spring is were I would start, especially since its unknown how many total rounds have been through the gun. Also give the chamber a good once over looking for any fouling that may be building up.

Regular replacement of the recoil spring is generally overlooked by most gun owners. Manufacturer suggestions vary but I replace mine every 2500-5000 rounds depending on the gun.

- Shawn

[Ronvandyn]

Thanks Shawn.  After posting that this evening I thought about that whole spacer idea and tossed it.  Seems to me that a spacer would prevent the slide from cycling fully, and of course a replacement part at MidwayUSA is just about $3.00.  Go figure.  For that price I think that's the way I am going to go.

Ron

[bullit]

As durable as those guns are, you can always use it as a back up hammer......

[Mudinyeri]

Just to be clear, the gun only does this with a round in the chamber?

[Ronvandyn]

Just to be clear, the gun only does this with a round in the chamber?

Actually its when trying to chamber a round into the chamber.

Ron

[Ronvandyn]

Well I double checked a few things on this problem.  The loads I was firing were pretty light, just target loads really, so I loaded a few near max load rounds and went off to the range.  Same problem.  I verified that the cases were properly sized when I loaded them so I knew that sizing was not the problem. 

Same problem.  *&_&%E!!!!  Well frack.  Went back to MidwayUSA and found that they sell non-manufacturer springs that are considerably stronger.  Wolf Slide Springs.  Never heard of them myself, but for less than $10 I can afford to experiment a bit.  Should be in this week, then off to the range next week. 

Ron

[Dan W]

Wolff gun springs are the best you can buy and they generally have sets that allow for stock replacement or others that are designed to fix problems

[Ronvandyn]

Wolff gun springs are the best you can buy and they generally have sets that allow for stock replacement or others that are designed to fix problems

Well Dan it didn’t fix the problem.  Blast it all.  I am putting it all down here to get it straight in my own head and maybe to get some advice from the old-salts that hang out here.

After another disappointing day at the range I came back to the house and pondered my problem.  I had a box of Winchester White Box ammo and decided to see if I had missed something.  Indeed I had.  50 rounds later without a mishap or stoppage of any kind I decided that I had missed something when I was reloading. 

I came back to the house and pondered some more.  The problem MUST be the casing, I know without a doubt that I am doing everything else correctly.  So I decided to map out the cases.  By that I mean I took my Micrometer and measured every single aspect of the cases, fired and empty, reloaded, and factory Winchester White Box.  Top to bottom, circumference, every which way I could think of.  One thing stood out. 

The reloaded rounds measure .472 at the top(where the bullet is seated), empty cases at .469, and factory loaded at .470.  At the bottom they all measure .470, even the reloaded cases. 

I am loading 200 grain LSWC’s from Missouri Bullet, who advertises on the box that they measure .452 in circumference (seems that all of their 45 auto rounds spec out to .452).  Not being a trusting soul I measured a random handful of the rounds, and they do indeed measure out to right at that size (within .001 variance of the 10 or so I measured).  Pretty close. 

Last but obviously not least is the thickness of the case walls.  I do not have the ability to measure that, at least not accurately.  But I have heard that some manufacturers make thicker case walls than others.  Makes some sense to me, but not much. 

So here is the question, the $64 one.  What is the maximum circumference of a 45 case, loaded, supposed to be, and since that seems to be the issue how do I fix it?

Ron

[Dan W]

Ron, I use a case gauge when I reload 45's, so I don't recall that case measurement. I do use a Lee factory crimp die on anything that fails the case gauging test.

But I do recall that 45 ACP is a straight walled case and I think that the crimp when correctly applied to the case will measure .469-.470" at the the top.

Sounds like you need more crimp.


But back in the first post you said that even factory ammo was giving you problems. Did the spring replacement remedy that issue?

Maybe you had more than 1 problem to deal with.

[justsomeguy]

http://www.saami.org/PubResources/CC_Drawings/Pistol/45%20Automatic.pdf

The Lee Factory Crimp die Dan mentioned should fix any crimp problems you may have.

An easy way to test your loaded rounds without a case gauge is to use the barrel of your pistol.
Just remove the barrel and drop EVERY loaded round in. They should fall all the way in freely, and when the barrel is upended, they should also fall out freely. You should NOT attempt to fire any round that does not pass this test.

[Ronvandyn]

Ron, I use a case gauge when I reload 45's, so I don't recall that case measurement. I do use a Lee factory crimp die on anything that fails the case gauging test.

But I do recall that 45 ACP is a straight walled case and I think that the crimp when correctly applied to the case will measure .469-.470" at the the top.

Sounds like you need more crimp.


But back in the first post you said that even factory ammo was giving you problems. Did the spring replacement remedy that issue?

Maybe you had more than 1 problem to deal with.

The heavy spring seems to have fixed the original issue with the factory ammo, but not with the reloads.  .469 to .470 is the measurements I am getting for everything but the reloads, and then only in the area where the round is seated into the case.  I never thought about a crimp die, not for pistols.  They dont come with the normal die sets for pistols like it did for my .223 Lee set I got a few weeks ago.  I'll give that a try.

I looked the barrel over real good last night after I cleaned it and there are no deposits in either the barrel or the chamber area that I can see, but as I am getting older and my eyesight isnt as good as it use to be I am not going to say 100% that there are not any.  The crimp die might just be the cure to this problem, I'll order one this week and let you guys know.

Ron

[Ronvandyn]

Cured!!!!   

It was a combination of not seating the round into the case far enough and the case mouth being to wide once the round was seated.  Those crimp dies are the BOM!

Went off to the range on Monday and put 100 rounds through it without any issues at all.  But dangit now I gotta buy some more lead.  A good problem to have I guess.   

Ron

[A-FIXER]

Cured!!!!   

It was a combination of not seating the round into the case far enough and the case mouth being to wide once the round was seated.  Those crimp dies are the BOM!

Went off to the range on Monday and put 100 rounds through it without any issues at all.  But dangit now I gotta buy some more lead.  A good problem to have I guess.   

Ron

Glad to hear that Ron... have fun.