Gunsmithing Q&A with Ken

kenBrooksOne of the benefits of being a member of the Gun Club of America, is the “Ask The Pros” forum on the GCA website. Ken Brooks, AGI Instructor and owner of Pisco Gunsmithing visits there regularly to help gunsmiths with particular problems they are experiencing. Here are his answers to some recent questions that may help you as well.

Question 1

Recrowning 22 rifles

Need a little help with a customer’s rifle. He wants me to re-crown it and so far (on practice barrels) I can’t seem to keep the chatter marks from forming. Will it damage the re-crowning work to simply polish it out with my Foredom tool? Thanks.

Ken’s Answer: First off how are you recrowning the barrel? If you clean it up without touching the area right at the bore it should be OK. Just do not alter the area where the bore meets the end of the barrel. Ken

Reply: I’m using the pilot crowning tool from the kit I bought from Brownells. My bench-top lathe is not big enough for rifle re-crowning. The chatter marks seem to be unavoidable with the kit-tool. I think it will be difficult to remove them without damaging, or at least “touching” the area at the bore-opening. Am I using the pilot crowning tool-kit incorrectly?

Ken’s Answer: Chatter often occurs using the hand crowning method. It shouldn’t as the cutter SHOULD be manufactured with the cutting edges different distances from one another. So the cutting edges don’t fall into a divot or depression caused by one of the other cutting edges and a repeat will occur causing the chatter. Regardless use the hand tool to square up the end of the barrel then use whatever you can that is UNIFORM to make sure the bore and the end of the barrel are even with one another. Polish the end of the barrel and away you go. Lapping is one method, using a round ball type cutter is another. Ken


Question 2

Ruger P85

Slide was stuck open and wouldn’t move until I noticed the barrel was probably too far to the rear. I think the barrel-lugs may be worn enough that it travels rearward too far when firing. Anyway, i used a plastic hammer on the barrel to move it forward and the slide went home. Though, now the slide won’t come off after pushing the slide-lock out for disassembly. I wonder if the barrel is keeping it from sliding off(?) I need to get it disassembled to determine if there is a problem with the barrel or lugs inside the top of the frame are worn too much to prevent this from happening. At least, I think that is what is happening… thanks for any input. I have a P95 that I’ve had for years and never had trouble like this with it.

Ken’s Answer: Sounds like the barrel was too far back and the slide stop didn’t get thru the link. Did you remember to lower the ejector down into the mag well to remove the slide assembly? If things are burred you may have to drive it off with a mallet. Ken


Question 3

‪Foredom tools?

Hello I’m just getting started on my gunsmithing courses and my Dremel broke I want to upgrade to a Foredom tool I have the catelog but my question is should I get the SR or TX series. The SR has a reverse option that I think would be great for control but 1/6 hp is that enough? Thanks

Ken’s Answer: Reverse is nice although I don’t use it often. I think the one I have is the SR. I like the #30 hand piece as well. I also advise you get the foot petal… I recommend the steel foot petal not the plastic one. The steel one simply lasts soooooooo much longer. Ken


Question 4

Springfield Armory XD Subcompact

From the videos I have seen on YouTube, on the SA XD models, the striker retaining pin is a hollow roll pin. A customer brought me his gun totally disassembled after having the slide and other parts coated with Cerakote. It had what I believe is the sear pin lodged in the top of the slide from his attempt to reassemble it. My question is – is the striker retaining pin actually a roll pin (there is one amongst the loose parts) ? If so, when removing the pin, the hole on the underside of the slide is smaller than the pin. So a punch would go into the hole in the pin instead of contacting the outer edges. So how would you remove the pin if the punch that fits in that smaller slide hole can’t push it out. It is removed with a punch in the videos, which makes me wonder how it could be a roll pin.

Ken’s Answer: It is a roll pin. Usually you can use a punch and cock it slightly to catch the side of the roll pin and drive it out, when one side of the hole is not as large as the roll pin. Ken


Question 5

Extractor rivet on old Rem 700 – how to do it?

I’ve replaced an extractor on an old 700, and aligned the rivet holes. Put the rivet in the hole and tried “mushing” it flat so as to hold the extractor in its’ slot. This Rivet is really hard and will not compress. What am I not understanding? It’s such a tiny thing, and sooo hard.

Also, is the head supposed to be on the inside of the radius or outside?

Is there a correct tool for this?

Ken’s Answer: There is a tool for installing the rivet in extractors. It holds the head against the extractor and therefore the extractor against the inside of the bolt lip. Then you peen the small leg that sticks thru the bolt with a hammer riveting over the rivet. The rivet should not be hard. Once the rivet is peened down and filling the small divot and rivet hole file it down flush with the outside of the bolt head. Ken

5 Responses to Gunsmithing Q&A with Ken

  1. Awesome. It’s been a long time since reading Q&A with Ken here on G&G. I miss them. Great to see this again. Thanks Mr. Ed!

      • You’re welcome. Of course no rush nor pressure or anything, just felt good to stimulate a temporary brain wake-up when trying to deduce the answers without ever seeing most of the guns the questions and answers are regarding. It’s like a mini test/quiz to me. Definitely learned something from the five Q&A’s. Thanks again,

  2. When using the Brownell’s muzzle facing and crowning tools, wrap the pilot in a piece of Brownell’s polyethylene parts bag before inserting it into the bore. Decent cutting oil, no more chatter.

  3. Great job, Ken. As always ,You seem to be able to visualize the problem without seeing the firearm. I’ll go out on a limb to guess that it is vast experience and superior knowledge!! Hope to see You at the shot show….Jim