Author Topic: Latch Engagement (Read 4970 times)

Fazak · « **on:** October 31, 2006, 06:35:28 AM »

Interesting commentary on the latch situation.

When I first got my Handi the frame latch was just barely engaging the lug on the barrel. Even snapping it closed smartly wouldn't allow the latch to engage but a small portion of the lug and the latch lever remained almost completely in the depressed condition.

Using a fine 1/4"X1/4"X 6" die polishing stone I slowly began polishing small amouts of material off the surface of the latching lug on the barrel (being very careful to hold the stone totally flat against the surface.) until, with the action closed the lever exhibits only about 1/16" of play.

Common sense dictates that one shouldn't stone the barrel lug until there is no play in the lever, but now the engaging surface of the latch has been increased from about 30% when new to approximately 80%

I can't wholeheartedly recommend that everyone work to increase the latch engagement of their rifles, but as a tool and die maker, I work with fitting close tolerance prts together on a daily basis,... and increasing the surface engagement of my latch immediately added consistency to my groups.

But again, I'm confident that my rifle came from the factory with less latch engagement than typical and just needed a bit of fitting.

Fazak · « **Reply #1 on:** October 31, 2006, 06:43:29 AM »

Along those same lines, I'm wondering if anyone has experimented with replacing the latch spring with a stronger example, or perhaps added a but of preload to the existing latch sping in order to increase lock up rigidity and conseqently, shot to shot consistency.

Fred M · « **Reply #2 on:** October 31, 2006, 08:11:15 AM »

Fazak.
Replacing the latch spring is nothing new, Some time ago I had a piece of spring made 12" long. The wire size was .036" compared to the factory size .032". I found that the new size was only margionally better. So I got another spring that fitted inside the larger one this is the system I now use and it works well.

I sold a few of these srings for $6.00 but I only had a few to sell. So why don't you make a sring winding jig and run some springs with 0.040" spring wire. That I think would be the best size and would not need another spring inside the main spring.

You can get a bit more compression by placing, a 0.060" washer in the spring seat hole.

The best job on the latch shelve is to shape it the same radius as the latch radius, that way the latch is supported fully and not just on the tangent point.

Fazak · « **Reply #3 on:** October 31, 2006, 08:26:42 AM »

Sounds interesting, Fred,... but I'll bet that spring stock like you've described is already out there somewhere. If I can get the outer diameter of the spring itself, I'll dig through some industrial supply catalogs to see.

quickdtoo · « **Reply #4 on:** October 31, 2006, 11:32:17 AM »

Fred's double latch springs work excellent, I have em on several of my high pressure calibers to include the .338-06A-Square and .280Imp-Imp. Latch work is covered in detail in the barrel fitting links in the FAQ and Help sticky.

Tim

Fred M · « **Reply #5 on:** October 31, 2006, 01:07:06 PM »

Fazak
The O.D of the spring is .248. The coils are about.095" c/c. I cut them to .700 an then fit to suit They end up about .670" long. Wire size should be .038" or .040 but I think the .040 would be best.

If you can find some chrome silicon springs that would be the ultimate, these don't relax.
They be more expensive but well worth the cost.

SHOOTER 72 · « **Reply #6 on:** October 31, 2006, 02:55:23 PM »

Fazak ,
if you make some i will bet there are a few people here that would be interested in purchasing them in the classifieds .

quickdtoo · « **Reply #7 on:** October 31, 2006, 03:06:14 PM »

Just so no one gets in trouble, please see the GBO Terms of Service in the Forum Announcements at the top of the index or the Classified rules in the Classified forums. Graybeard is very strict on what can be sold by a member.

Thx,

Tim

Fazak · « **Reply #8 on:** October 31, 2006, 09:12:44 PM »

Just got home from work.

I've written down the dimensions to the spring and I'll check around to see what's available. My first guess is, it's not going to be too difficult to loocate. The .248" O.D. of the spring is undoubtedly a nominal 1/4" diameter. An industrial supply house named 'McMaster Carr' stocks so much related articles that it's difficult to conceive of something along those lines which they don't have. The only problem is navigating their catalogue.

I dug into my gun spring collection to see what I had which may work and the closest I've found is a hammer return spring from an FN-FAL,..... but I'm guessing that it's going to have too large of an O.D. to function as a latch spring for a Handi.

It's a fairly stout little spring with an O.D. of .267", a wire diameter of .048" and the coils are spaced about .090" apart center to center.

Close,... but probably no cigar.

I'll dig around and get back with you, Fred.

By the way,... I'm not here to sell anything. If I can locate the springs,.. or anything else which may be of assistance to anyone, I'll simply pass the information along as to where it can be obtained.

Fazak · « **Reply #9 on:** October 31, 2006, 09:27:51 PM »

OK, Fred,.... go here

http://www.mcmaster.com/

Type in "springs" in the search window.

Select "compression springs" from the resultant menu which comes up.

There's a table which lists O.D., wire diameter, and length.

Here's part # 9657K231 which is .250" in diameter and rolled from .041" wire, 2" long.

$8.55 per pack of 6.

Fred M · « **Reply #10 on:** November 01, 2006, 07:28:31 AM »

Fazak
Thanks for the info. I just ordered a set of these springs to try them out. They are cheap enough for testing. The bottom of the seat hole can be lowered to reduce the compression a bit if needed.

northjdr · « **Reply #11 on:** November 01, 2006, 07:41:13 AM »

I was looking at the rough drawing of the latch in the barrell accurizing FAQ but my latch doesn't look like the drawing. The recess on my 308 barrel lug appears to be a 90 degree notch not a rounded surface. Should the latch be engaging at least 1/8" into this recess? If it isn't engaging that much would you gradually stone material from the bottem edge of the lug recess until you got to the desired engagement?

trotterlg · « **Reply #12 on:** November 01, 2006, 01:51:17 PM »

Be very careful removing material from the latch shelf. The amount of engagement is limited by the latch travel, you may run out of latch travel before you get half of the shelf engaged, I have done this, cost me a barrel. Larry

SHOOTER 72 · « **Reply #13 on:** November 01, 2006, 04:15:01 PM »

fazak ,
i was not trying to suggest that you sell anything , some people like to do that sort of thing with parts or upgrades . i guess i should have kept my thoughts to myself .

quickdtoo · « **Reply #14 on:** November 01, 2006, 04:25:44 PM »

Quote from: Fred M on November 01, 2006, 07:28:31 AM

Fazak
Thanks for the info. I just ordered a set of these springs to try them out. They are cheap enough for testing. The bottom of the seat hole can be lowered to reduce the compression a bit if needed.

Me too!! Thanks Fazak!!

Tim

Smokin Joe · « **Reply #15 on:** November 04, 2006, 04:57:13 AM »

I ordered one of the spring packs. Has anyone tried them yet? If so, what were the results?

quickdtoo · « **Reply #16 on:** November 04, 2006, 09:23:57 AM »

Mine were shipped Wednesday, haven't got em yet, probably won't until next Wednesday.

Tim

Ricci Price · « **Reply #17 on:** November 08, 2006, 09:48:44 PM »

Trotterlg, the latch can be hammered back in to fitting again I think this is how they fit them at the factory this can be seen in that video about the H&R factory that was posted sometime back. I had to hammer my 25-06 latch after I rebuilt the lug on it I also built a 45 cal. muzzleloader barrel I built the latch(barrel lug) with a full circle at the pin end made it out of 4340 and also had to hammer it. I will probably redo the 25-06 lug again with 4340.

quickdtoo · « **Reply #18 on:** November 11, 2006, 01:51:56 PM »

Got my springs today, the indicia on the package indicates they mailed it on Nov 1st, but 10 days from southern California by parcel post is not real, 5 days yes, I think they never took it to the PO to be mailed until much later. They also over paid postage on the 13oz package by at least $3.50 with $7.35 postage on the package, they apparently don't ship by mail often and use UPS, but I prefer mail to my po box, but I did offer them an alternative UPS street address, but they didn't use it. They could have mailed the 6 springs in a small padded envelope for less than a dollar and just threw it into their outgoing mail! They only charged $4 shipping so they really messed up.

The great news is the springs work great, I think 3 springs ~.600"-.575" long out of each piece will do the trick, any longer and the spring won't compress enough to release the barrel. As it is, it takes considerable strength to release it! That length works if the spring pocket bottom is squared up to a depth of .300", without doing that, the spring needs to be much shorter.

I did a trigger job on the frame while I was at it since I had never done one on it, was 4½lbs which was just acceptable to me for a hunting rifle, now it's at 2lbs-6oz!!

Thanks Fazak!!

Tim

Smokin Joe · « **Reply #19 on:** November 11, 2006, 03:34:35 PM »

That's good news! I guess I'm gonna have to get out the Dremel and start cutting springs.
They did the same to me re: shipping............1 oz spring pack in an 8 buck box; it arrived in 3 days, though