|
|
Joined: Dec 2002
Posts: 22,274
Campfire Ranger
|
OP
Campfire Ranger
Joined: Dec 2002
Posts: 22,274 |
I like my PSA 6.5 Creedmoor. It shoots better than either of my .308 AR-10's, and after some tuning, works reliably.
Once obvious gripe is there's a lot of slop between the upper & lower, at the takedown pins. Has anyone ever identified accuracy improvement, by reducing this play?
If worthwhile, does someone make oversized pins, that could tighten up the fit?
"...the designer of the .270 Ingwe cartridge!..."
|
|
|
|
|
Joined: Oct 2014
Posts: 4,755
Campfire Tracker
|
|
Campfire Tracker
Joined: Oct 2014
Posts: 4,755 |
That slop is a relatively easy thing to fix, so i do it on any of my ARs that need it. Don't know if it really improves accuracy much but it sure doesn't hurt.
I bed the upper and lower together with "ultra black" RTV from the auto parts store. I use that stuff instead of hard epoxy because I get better results removing all of the rattle. Use release agent on the upper, and apply the RTV to the lower in the curve at the rear and at the front between the magwell and front pin.
Using some method of forcing the upper and lower apart while the rtv cures is important to a tight fit. I use an O-ring around the front lug of the upper. This results in a rock solid fit after the RTV cures, and the RTV has just enough compliance that you can still get the takedown pins in and out easily.
|
|
|
|
|
Joined: Aug 2010
Posts: 48,198 Likes: 22
Campfire 'Bwana
|
|
Campfire 'Bwana
Joined: Aug 2010
Posts: 48,198 Likes: 22 |
Why not just use an acu wedge?
I try to stick with the basics, they do so well. Nothing fancy mind you, just plain jane will get it done with style. You want to see an animal drop right now? Shoot him in the ear hole. BSA MAGA
|
|
|
|
|
Joined: Oct 2014
Posts: 4,755
Campfire Tracker
|
|
Campfire Tracker
Joined: Oct 2014
Posts: 4,755 |
Why not just use an acu wedge? If you're asking me, that's an option too but I like the feel of a bedded receiver set better. It's only a couple minutes of work, not like it's a big deal to do.
|
|
|
|
|
Joined: Oct 2013
Posts: 18,952 Likes: 2
Campfire Ranger
|
|
Campfire Ranger
Joined: Oct 2013
Posts: 18,952 Likes: 2 |
That slop is a relatively easy thing to fix, so i do it on any of my ARs that need it. Don't know if it really improves accuracy much but it sure doesn't hurt.
I bed the upper and lower together with "ultra black" RTV from the auto parts store. I use that stuff instead of hard epoxy because I get better results removing all of the rattle. Use release agent on the upper, and apply the RTV to the lower in the curve at the rear and at the front between the magwell and front pin.
Using some method of forcing the upper and lower apart while the rtv cures is important to a tight fit. I use an O-ring around the front lug of the upper. This results in a rock solid fit after the RTV cures, and the RTV has just enough compliance that you can still get the takedown pins in and out easily. Any pics?
The last time that bear ate a lawyer he had the runs for 33 days!
|
|
|
|
|
Joined: Aug 2010
Posts: 48,198 Likes: 22
Campfire 'Bwana
|
|
Campfire 'Bwana
Joined: Aug 2010
Posts: 48,198 Likes: 22 |
Why not just use an acu wedge? If you're asking me, that's an option too but I like the feel of a bedded receiver set better. It's only a couple minutes of work, not like it's a big deal to do. I was just asking as a general question. I don't hear a lot about them here. However, I use them and they work great. I've seen groups shrink a little by using the accu wedge. Their main purpose is to fix upper to lower slop though..
I try to stick with the basics, they do so well. Nothing fancy mind you, just plain jane will get it done with style. You want to see an animal drop right now? Shoot him in the ear hole. BSA MAGA
|
|
|
|
|
Joined: Jul 2009
Posts: 8,923
Campfire Outfitter
|
|
Campfire Outfitter
Joined: Jul 2009
Posts: 8,923 |
That slop is a relatively easy thing to fix, so i do it on any of my ARs that need it. Don't know if it really improves accuracy much but it sure doesn't hurt.
I bed the upper and lower together with "ultra black" RTV from the auto parts store. I use that stuff instead of hard epoxy because I get better results removing all of the rattle. Use release agent on the upper, and apply the RTV to the lower in the curve at the rear and at the front between the magwell and front pin.
Using some method of forcing the upper and lower apart while the rtv cures is important to a tight fit. I use an O-ring around the front lug of the upper. This results in a rock solid fit after the RTV cures, and the RTV has just enough compliance that you can still get the takedown pins in and out easily. I have a few of the Accuwedges and they take out the slop fine, I wonder if a few layers of electrical tape betweent he upper and lower would do the same as bedding.
Dave
|
|
|
|
|
Joined: Dec 2002
Posts: 22,274
Campfire Ranger
|
|
OP
Campfire Ranger
Joined: Dec 2002
Posts: 22,274 |
okay, had not heard of an accu wedge before; need to try one 
"...the designer of the .270 Ingwe cartridge!..."
|
|
|
|
|
Joined: Nov 2006
Posts: 10,189
Campfire Outfitter
|
|
Campfire Outfitter
Joined: Nov 2006
Posts: 10,189 |
Why not just use an acu wedge? Some of the SME's on another forum talked about them breaking down an having the potential to come apart and get in the trigger. I have had one in a particular gun for over 10 years now. I call BS on them breaking down but I don't use them in any of my other guns. The sloppy fit is no problem except in your mind. If it bothers you then use one or bed it. Or slide an O ring over the front lug on the upper. I think rost495 said bedding a gun only showed slightly better accuracy at 300 yards.
|
|
|
|
|
Joined: Jun 2006
Posts: 75
Campfire Greenhorn
|
|
Campfire Greenhorn
Joined: Jun 2006
Posts: 75 |
National Match Shim http://www.wheeldiamond.com/nationalmatchshim.htmTakes 15 minutes or so to fit to your upper and lower for a fit as tight as you want. Clarence
|
|
|
|
|
Joined: Jan 2005
Posts: 57,494
Campfire Kahuna
|
|
Campfire Kahuna
Joined: Jan 2005
Posts: 57,494 |
If I feel the need, I bed ours with Steel Bed or JB.
They feel better.
I've done quite a bit of shooting, as did John Feamster in the 90s.
My take, that at 300 yards, you got about a bit better group size overall, IIRC, 10 shot groups shrunk maybe 1/4 inch or a bit more. They did become much rounder though and shot dispersion was much more centered rather than who knows how far each shot might stray from the very middle so to speak. Hard to really describe and I dont' have any of the photos anymore of all the testing.
That said, I would only do it on a "match" gun, not a hunting gun, 3 gun gun etc... just strictly were the most accuracy mattered.
We can keep Larry Root and all his idiotic blabber and user names on here, but we can't get Ralph back..... Whiskey Tango Foxtrot, over....
|
|
|
|
|
Joined: Oct 2014
Posts: 4,755
Campfire Tracker
|
|
Campfire Tracker
Joined: Oct 2014
Posts: 4,755 |
That slop is a relatively easy thing to fix, so i do it on any of my ARs that need it. Don't know if it really improves accuracy much but it sure doesn't hurt.
I bed the upper and lower together with "ultra black" RTV from the auto parts store. I use that stuff instead of hard epoxy because I get better results removing all of the rattle. Use release agent on the upper, and apply the RTV to the lower in the curve at the rear and at the front between the magwell and front pin.
Using some method of forcing the upper and lower apart while the rtv cures is important to a tight fit. I use an O-ring around the front lug of the upper. This results in a rock solid fit after the RTV cures, and the RTV has just enough compliance that you can still get the takedown pins in and out easily. Any pics? This one looks uglier in the pic than in person. You can't tell it's bedded when the receivers are pinned together. rost495, why are you saying to only do this to a "match" gun? I've never found a reason not to do it to all of them, if only because I prefer my guns not rattle. ![[Linked Image]](https://i.imgur.com/mf1WUmc.png)
|
|
|
|
|
Joined: Jan 2005
Posts: 57,494
Campfire Kahuna
|
|
Campfire Kahuna
Joined: Jan 2005
Posts: 57,494 |
It makes such little difference and I could care less about the fit of the gun, looks of the gun or some minor slop in the gun. Thats the only reason, well that and you have mated it permanently basically, ( until removing the bedding) to whatever lower you have it on. Not that I have a shortage of lowers, but I don't always have as many lowers running as I have uppers.
It takes a bit of work granted, not much, but enough such that the results to me aren't worth the effort.
Thats about it.
How you run yours are cool with me too!
We can keep Larry Root and all his idiotic blabber and user names on here, but we can't get Ralph back..... Whiskey Tango Foxtrot, over....
|
|
|
|
|
Joined: Oct 2014
Posts: 4,755
Campfire Tracker
|
|
Campfire Tracker
Joined: Oct 2014
Posts: 4,755 |
Thats the only reason, well that and you have mated it permanently basically, ( until removing the bedding) to whatever lower you have it on. That makes sense rost. This quoted bit though reminded me of another reason for using RTV instead of hard epoxy - there's still some interchangeability with different uppers. Not all will fit or be tight of course, but some of them will. Several of mine bedded this way get swapped around.
|
|
|
|
|
Joined: Nov 2006
Posts: 10,189
Campfire Outfitter
|
|
Campfire Outfitter
Joined: Nov 2006
Posts: 10,189 |
An O-ring over the front lug and an accuwedge beats not having to smell RTV and put up with the mess.
|
|
|
|
|
Joined: Oct 2014
Posts: 4,755
Campfire Tracker
|
|
Campfire Tracker
Joined: Oct 2014
Posts: 4,755 |
Oh please. If a dab of RTV bothers you that much, stay in the kitchen. Are we talking about working on guns here, or having a tea party?
|
|
|
|
|
Joined: Jan 2005
Posts: 57,494
Campfire Kahuna
|
|
Campfire Kahuna
Joined: Jan 2005
Posts: 57,494 |
RTV does wonders as a gas seal on the charging handle though...
We can keep Larry Root and all his idiotic blabber and user names on here, but we can't get Ralph back..... Whiskey Tango Foxtrot, over....
|
|
|
|
|
Joined: Nov 2006
Posts: 10,189
Campfire Outfitter
|
|
Campfire Outfitter
Joined: Nov 2006
Posts: 10,189 |
Calm down there Fluffy, I deal with the crap everyday and I can't find any reason to use it on my guns.
|
|
|
|
|
Joined: Dec 2004
Posts: 14,488
Campfire Outfitter
|
|
Campfire Outfitter
Joined: Dec 2004
Posts: 14,488 |
RTV does wonders as a gas seal on the charging handle though... I'd like to know more about this...assuming you're serious, of course.
Don't be the darkness.
America will perish while those who should be standing guard are satisfying their lusts.
|
|
|
|
|
Joined: Jan 2005
Posts: 57,494
Campfire Kahuna
|
|
Campfire Kahuna
Joined: Jan 2005
Posts: 57,494 |
release agent on upper where charging handle locks in place, RTV on charging handle, close handle barely, with backward tension on it, let cure. Trim as need be. Does a good job if you have a wind blowing in your face for sure...
I'm sure someone will have pictures to post.
We can keep Larry Root and all his idiotic blabber and user names on here, but we can't get Ralph back..... Whiskey Tango Foxtrot, over....
|
|
|
|
|
551 members (1minute, 06hunter59, 219DW, 21, 204guy, 10Glocks, 62 invisible),
2,576
guests, and
1,228
robots. |
|
Key:
Admin,
Global Mod,
Mod
|
|
|
Forums81
Topics1,193,600
Posts18,511,464
Members74,002
| |
Most Online11,491
Jul 7th, 2023
|
|
|
|
