Keep me posted on how it works. I think to double your efforts you could do what your doing now with the set screw and block the gas tube for a double whammy. I just have not figured out what would be the best way to do that yet as the slide assembly goes up to the gas tube so you want the end to be the same you would have to fill the tube somehow with something. I thought maybe a brass rod inserted into the gas tube?
A gun is like a parachute: If you need one and don't have one, you won't be needing one again.
I think your idea of plugging the barrel gas port is the way to go. I wouldn't attempt to plug the tube with anything--it points backwards at the shooter.
I was quite surprised when my reduced load of 20 gr. of 4759, 80 gr j-word, nearly cycled the action even though it was partly plugged. The gas pressure at the port had to have been far lower than my usual loads of much slower powders.
US out of the UN, UN out of the US.
Seems like you could use the same idea to reduce the gas flow till it will just barely cycle and reduce or eliminate the problem.
Yea I think if you get the right thickness of the set screw right it should not cycle mine did not.
A gun is like a parachute: If you need one and don't have one, you won't be needing one again.
What I have found, the first sign of trouble is jerking the cheaply made extractor out of the bolt.
The guns were made when powders were slower. I coned down the gas port to restrict the rear violent movement of the bolt.
There are two theories to arguing with a woman .. . Neither works.
Women always say that giving birth is way more painful than a guy getting kicked in the nuts.There is no way to prove that they are wrong.
But a year or so after giving birth a woman will often say "It would be nice to have another child".
You never hear a guy say, "It would be nice to get kicked in the nuts again".
Thats interesting but does it still slowly wear the receiver? I figure if it does not recycle at all then the receiver and other parts is not going to get the stress of the violent slamming that causes the problems in the first case.
A gun is like a parachute: If you need one and don't have one, you won't be needing one again.
Oh yeah, I'm sure it does, but you can get a few more rounds out of it. Or at least til you can trade it off.
There are two theories to arguing with a woman .. . Neither works.
Women always say that giving birth is way more painful than a guy getting kicked in the nuts.There is no way to prove that they are wrong.
But a year or so after giving birth a woman will often say "It would be nice to have another child".
You never hear a guy say, "It would be nice to get kicked in the nuts again".
Which is why I altered mine not to cycle at all that way it should last just like a 760 does. No sense it trading it off as most folks now days know about the issue and will not give you squat for them anyway. Besides for me the gun was given to me and I told the guy I would not sell it or trade it off since he did make a gift out of it to me.Originally Posted by johnlaw484
Oh yeah, I'm sure it does, but you can get a few more rounds out of it. Or at least til you can trade it off.
A gun is like a parachute: If you need one and don't have one, you won't be needing one again.
well... now i know why the ol' boy was trying to sell that 742 fer 100 bucks...
glad i read this thread.
but i have no troubles with my 06' 7400
UPDATE:
Here's some data on my port-restriction efforts so far. I want to end up with enough port-area to allow "gentle" extraction and ejection.
My Remington 7400 .243 has a port dia. of 0.076", which gives a cross-sectional area of 0.0045 sq. in. First I tried a socket head capscrew that I cut the end down to 0.060" where it was within the port. That reduced the port flow area to 0.0017 sq. in., which is only ~30% of the orig. area.
Fired one round; load was "moderate" power with 31 gr. AA2520 behind a 100 gr. j-word. Full ejection which threw the brass ~3' away.
Changed the capscrew to one with a dia. of 0.073", which gave a flow area of ~0.00035 sq. in., or ~8% of the orig. Same load, no extraction.
Now I'll make some more screws with dia. ~0.070" and 0.065" and try them.
US out of the UN, UN out of the US.
Took the rifle up to Prescott where it was cool enough to shoot, and tried a screw-plug that miked .0665", for a flow area of ~23% of the original.
Results were mixed with light/moderate loads that developed ~1300 ft. lb energy with 100 gr. j-bullets vs. a factory loading of ~1870 ft. lb. from a 22" barrel. Most rounds did not eject. The bolt extracted the fired case enough that it turned sideways and the bolt then hit it amidships. One case did get ejected and thrown ~2' away, but the bolt did not latch and returned to battery--magazine was empty.
I'm sure that bolt cycling would be normal with full power loads, so next I'll make a screw with a dia. of ~.069-.070" and see what happens.
Amazing how such a small port area will still make the rifle function.
US out of the UN, UN out of the US.
Interesting. Yea I suspect full power loads would eject ok.
A gun is like a parachute: If you need one and don't have one, you won't be needing one again.
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