DSA heavy duty scope mount PROBLEMS

[jaykden]

ok, awhile back i bought a DSA heavy duty scope mount off a member here.

everything came in grat condition.


anyway, i have it mounted on an imbel receiver and lately the screws have been loosening up.

so i tighten them. then last week i was shooting, after i was finished i opened the action and a thin piece of steel fell out. i looked inside and one of the steel clamps broke.

i thought, 'hmmmmm thats odd'

anyway, i made sure all the screws were tight and went back out. it happened AGAIN with two more clamps.

i looked inside at the remaining clamps and only one is ok, as in straight up and down.

the other one is BENT like i tightened the screws too tight and its binding against the rails of the receiver (lower part of clamps angles toward and touches the bolt carrier).



the questions i have are:

- is this my fault for tightening the screws too tight, if so, is there a torque setting i need to know?

-do these receivers not fit the rails of imbel receivers?

i'm going to call DSA and have them send me more clamps, but i want to know whats up before i tighten them on again.

[Radio]

When DSA was selling SUITs some years ago, the mount they sent with the scope was one of their own scope mounts with the Picatinny machined to accept the SUIT "T" mount.

Right away this went on a Gear Logo IMBEL and (unfortunately, but that's just the nature of the beast) scratched the chit out of the receiver. Anyway, four little steel inserts that grabbed the inside of the receiver, two screws each, eight screws total. Had some problems at first until I understood that one of the steel inserts was SLIGHTLY COCKED. Backed off the screws, jabbed my rather pudgy finger in there and straightened it out, all was well.

As of 2000 the screws were simple flat-blades, so there is a "limit" to the amount of "torque" one can apply before beginning to round out the screw heads, but let's just say they were pretty snug. I would assume any reasonable torque appropriate for the shank diameter of the screw would be acceptable... you won't need 100 ft-lbs for example.

That DSA mount stayed on my rifle TIGHT as long as I kept it there. Never noticed the screws backing out, but in this case I would think something simple like LocTite would solve a world of problems.

Hope this helps,
--Radio

[W.E.G.]

Sounds like you ruined several of the locking plates, and probably the screws.

I guess you missed the lecture(s) where we talked about the necessity of using LOCTITE on the screws.

The plates only have about three threads for the thickness. You know you can't put but so much torque on such a thing before you strip it.

Degrease before applying LOCTITE.

[jaykden]

gotchya



loctite and tighten till snug, WITHOUT over tightening. i'll order more plates tomorrow and start over.



lesson learned, thanks.

[stevem]

I've broken a couple of those suckers too. On my mount, the screw holes are large enough that the ridge on the bottom of the locking plates can ride up above the groove in the receiver. Tightening them up when they're out of alignment seems to be when they fail. I've started checking them all with a flashlight before I dog'em down.
S.

[Dunk RD]

very first DSA scope mount I installed, I did not have the bottom of the plate in the grove in the receiver. Split two plates.
From then on I check carefully that they are in the grove. No more have ever broken.

Dunk RD

[jaykden]

i have always made sure they were properly lined up by looking in the receiver and also by sliding my fingers along the inside to feel that they were flush.


from what gary said, i think what happened is i just cranked on them too tightly (to make up for what loctite does) and the thin plates came up against the rails and just bent from too much torque being applied to the screws.

[Rocket 6R]

I've used mine on and off for about five years. I have had it not loose zero. I have had Eotech's on it and 22oz tactical scopes on it. I place the mount on the rifle and install the plates and screws. I also put a little of blue loctite on the screws. I hand tighten the screws and then check to make sure that the bolt carrier is not rubbing on them. I have had this mount on two FAL's (imbel receivers) and it has never came loose. You can purchase additional plates and screws from DSA.

Good Luck, Rocket 6R

[EricCartmanR1]

i was not going to use loctite on my mount but it came with loctite so a lightbulb flashed over my head... "maybe i should use the loctite" been on for over a year now and no problems

[jaykden]

thanks for the input guys, i have plates and screws on the way.

[thanatos56]

Originally posted by W.E.G.
Sounds like you ruined several of the locking plates, and probably the screws.

I guess you missed the lecture(s) where we talked about the necessity of using LOCTITE on the screws.

The plates only have about three threads for the thickness. You know you can't put but so much torque on such a thing before you strip it.

Degrease before applying LOCTITE.

I got this thing about screw heads and blade screwdrivers...

A few years ago, I bought a box of 8-32x1/4" button head cap screws, with a torx head. Seems like I paid $10 for the box of 100 through a machine screw house, online. Replaced ALL of those screws in ALL of the mounts, plus some other miscellaneous screws.

Have never used Loctite, but... I admit to checking the screws for tightness every time I have cleaned a rifle.

And, yanno? Those torx head cap screws are EVER so much cleaner. (And MUCH less expensive than what DSA wants for them...)

[shootist87122]

The GPG 5th generation mount is a better design, IMO. Fits into the dust cover groves tight - almost too tight in some receivers. There are no internal plates to come loose and flop about, either. I rate it up there with the Williams, although it's not as sleek looking.

[welding inspector]

Which mount allows the lowest mounting of scope?

[shootist87122]

jaykden - I apologize for the hijack, but (IMO) DSA really needs to invent a better mousetrap.

Inspector,

The GPG mount will allow you to mount lower than the DSA since it sits a little lower and the grove running down the center of the rail will actually permit the scopes's rear bell to sit slightly lower than the rail. Tactical Tim's M4 Leupold Tactical (1.5x5) went on with med rings due to this feature. However, It's an easy job to mill off a few of the rearmost slots on the DSA mount to gain some room for the rear bell. I had to do that on one I had to get a Burris Compact down low.

If you don't have enough eye relief to keep the rear bell in front of the rear sight it's a moot point, so choosing the right scope is also important.
I'll see if I can get Tim to send me a pic of his setup to post in the optics section. It's working even better than we expected on his G1 with free floated Vandenberg HGs.

The pics below is my Leupold 3x9x33 Compact on a GPG mount. The rear bell sits just over the front edge of the rear sight base. The limiting factors here was the rear setup as well as the front bell, as it just clears the hand guards. The Leupold Tactical has even more eye relief and mounts a slot or two further forward.

pic quality of my Imbel is not the best here due to the bright NM sun that day:


A nicer pic after I moved the setup to my StG/3-Gun Rifle: (I do not remove the mount when cleaning the rifle.)



Some proof that the setup works. These were taken as I was sighting it in (sorry again for the quality of the pic).

[thanatos56]

Originally posted by shootist87122

The GPG mount will allow you to mount lower than the DSA since it sits a little lower and the grove running down the center of the rail will actually permit the scopes's rear bell to sit slightly lower than the rail. Tactical Tim's M4 Leupold Tactical (1.5x5) went on with med rings due to this feature. However, It's an easy job to mill off a few of the rearmost slots on the DSA mount to gain some room for the rear bell. I had to do that on one I had to get a Burris Compact down low.

Let us give credit where credit is due... While I have only the highest regard for James (GunPartsGuy), that is actually the Tapco mount, and not a mount that James designed/manufactured.

Using the DSArms mount? I have had to taper both the front and the rear of the mount (for the scope bells), plus clearance a section from the handguards (because the bell of the scope made contact with the handguard), AND grind down into the rear sight base, after the sight itself had been removed.

I have no "special love" for DSA - and have had various "issues" with them - but, in "fairness", ten screws are better at keeping the scope mount secure than are four. And having used both the DSA and Tapco mounts, I will continue to reluctantly send my money to DSA.

[shootist87122]

10 screws means you are forcing something to fit where it's otherwise sloppy? FWIW, I could never get better groups with my DSA mount than I could with the irons. (YMMV squared.)

Not surprised to have someone come along and piss on the GPG/Tapco mount as I was VERY reluctant to try one (now two) myself, but I have used both the commie made mount and the DSA, and the proof is in the pudding. YMMV one more time. Tim was doing "4 corners" on the 500M gong with his last week - amazing for a FAL and that makes three successful rifle/mount tests out of three. [I previously indicated they sometimes fit so tight [to the upper receiver] that some fitting might be required - that's a good thing, btw.]

If a comparable US made version, like my Williams SL mount, were still available I would have been all over it, but sadly that's not the case. Different FAL (the Imbel in the above pic which btw has a preference for SA R1M1); same mount (& more pudding) - with Aussie (10 shot group): As they say "a pic is worth a thousand words".

[Radio]

Originally posted by NoNotAgain
if Loctite is not available, good ole clear nail polish on the screws works fine and is removable with acetone.

And some say there are NO advantages to living with a woman.

--Radio