Follow Trent Griswold with Griswold Brothers Gunsmiting and Ballistics Research Group as he cuts down, crowns and threads a precision barrel in a lathe from start to finish.
Thank you Lana! We've had our share of influential people come through the shop and I must say, hanging with Dick was definitely a highlight. Especially the karate lesson he gave us. LOL. Thank you for sharing him!
@@trentgriswold A music pioneer/creator legend all the way and like a son to Leo Fender. Pioneered all of the fender equipment with Leo and yes, the greatest of the Greatest souls ever. My husband was forever beyond the beyond!!!!
I've had you work on several of my guns in the past and have always been very happy with the outcome. I'm going to be bringing in a rifle for rebarreling end of May beginning of June and I can't wait. this was an interesting video to watch.
Great to have you here! Glad to see you in the shop. I would like to request a video on some of your unique gunsmithing tools that you don’t see that often (passed on by other smiths) or tools to and your brother made yourselves.
Thanks man! Been meaning to reach out. Lots of requests for original GBG shirts. People have always been stoked on that artwork. Our screen printer had our artwork archived and they closed up shop. Gotta figure out how to get that goin again!
just starting out in the industry (still in school) but one of my primary planned projects is to set up an AK to run suppressed, and do so flawlessly. One of the challenges as you may know, is the lack of concentricity in the 14x1LH threads on most AK's. rethreading to a more common pitch and ensuring concentricity IMO is the best way forward on such an endeavor.
I have just run across your video I can tell you from someone who’s just starting out appreciate anything you will show a video I understand the process and have already chamber tomorrow and done fairly well but I like to learn all I can learn and I hope since this is what you’re doing that maybe I’ll pick up some tips from you So I will be watching all your videos and appreciate anything that you will be putting on in the future thank you again
How did the shorter barrel and new crown affect your accuracy and velocity from before? I’m considering cutting and doing the same to my barrel on a 6.5 SAUM but a bit worried about accuracy and speed after it’s done.
The accuracy increased. Many people correlate velocity with accuracy and that’s simply not the case. A shorter barrel is more rigid and has less “whip”. With that said there are reasons for wanting or needing higher velocity, stability at extended ranges or just in general, expansion or penetration etc. But for instance, many of the bolt guns we build for LE swat teams are shorter than 20” and as short as 14” due to them not typically engaging targets over 75 yards. I still shoot my 20” .308’s well past 1000yds. You just need to way all those options and come up with a formula that fits your mission. If you don’t need it shorter and it already meets your accuracy needs I would probably leave it as is. I do plan on doing a video measuring the loss of velocity when cutting down at some point.
I have a question after watching this and your other videos. If you have a barrel that you can't remove from a receiver (heat interference fit), are you still able to cut and thread on a lathe? I guess it depends on the depth of the head stock. Particularly, I have a VZ58 with a 15.4" barrel that I want to chop down a few inches and properly thread it with regards to concentricity for use with a suppressor. I've thought about going the DIY route, but I'm thoroughly impressed with the workmanship of professionals like yourself and don't know if I'd do it justice.
Great question. Many times if you have access to the breach end of the barrel through the receiver you can use a mandrel. I do that quite frequently on bolt guns and in some cases AR style uppers if the client doesn't want the barre removed for a number of reasons. Since you don't have access to the breech end of the barrel on a ZV58, you could chuck up the receiver and use a steady rest and or brass live center on the barrel I suppose. I'd probably go the piloted crowning tool route on that as you wouldn't be expecting bench rest accuracy anyhow.
Ok dont you need to engage the half nut on a certain number everytime, or can you just skip that part and leave it on the lead screw all the time? Thanks and awesome video
Good observation. You can most certainly leave it engaged the whole time. On that particular lathe, it depends on the thread you are cutting as far as when to engage. You can actually engage on any number for 1/2x28 threads. Not the case on many other lathes. Thanks for watching!
Couple questions: Why not use the micrometer measure the barrel OD? Why did you face the barrel on the opposite side? I assume the tool was also upside down? Thanks
Its a just used a radius on a piece of round brass stock. You can buy brass laps pre made but they are cheap and easy to make. I use Clover lapping compound by loctite. Both the 600 and 800 grit work well.
It varies quite a bit depending on weather it’s just threads and the barrel can stay on the action or a full cut and crown, as well as type of barreled action etc. Ballpark anywhere from $150-$225.
Ask whomever taught you that a left had lathe tool cuts right to left for a refund. I’ll give you a free tip after nearly fifty years in the trade. If you want to cut threads close to a shoulder flip a left hand threading tool upside down and cut left to right with the lathe in reverse. It eliminates the panic mode as the tool nears the shoulder, the tool just passes cleanly off the end of the part. you can take a narrow grooving tool and cur a shallow relief at the shoulder and advance your tool into it before engaging the half nut.
@@funnytimes1262 some pistols are made of stainless and some are made of chromoly steel. Same goes for rifle barrels. The parts of most firearms vary greatly as far as their alloy depending on their function. For example, locking surfaces that are high friction need to be extremely hard and might be a different alloy and heat treat than another part. Hear treat is also another important aspect. A firing pin is case hardened with an extremely hard exterior but if the entire firing pin was hard it would be to brittle and shatter. So it’s case hardened to have a hard exterior to keep from deforming but soft and flexible inside as not so shatter or crack.
Great question. Because it’s in a Four Jaw and “dialed in” in don’t want to disturb how it has been set up. If it was just a Three Jaw chuck torqued down nice and tight I could take larger bites. Thanks for watching!
