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Discussion Starter · #1 ·
Looking for some advice regarding a Remington 740 autoloader in 30-06. This is my Grandpa's old gun that my cousin recently had. The gun used to have a sidemount for the scope which my cousin had replaced with peek-through rings (which suck but I don't think it's the issue). A couple weeks ago I had a conversation with my cousin and he told me that since he has had the gun back from having the new rings put on it he can't get it sighted in or even keep it on paper. Well I have the time and place to mess with it so I said I'd take a look at it. Today I took the gun to the range. First two shots @ 25 yards were touching (150 grn Rem Core-Lokt PSP) so I put the target out to 100 yards. 3 shot group just over 1" .... perfect. Well, I also brought along a box of Hornady SST Interbond 150s. Shot 3 times, group was the size of a basketball @ 100 yards. I let the gun cool for 20 minutes or so, shot another group....again size of a basketball. I was initially thinking it just didn't like those bullets so I shot another 3 core-lokts....group was again all over the place.

The only thing I didn't do was brush the barrel out or run any fouling cleaner down it, but I can't imagine it got that fouled after just 10-15 shots. I know I'm not flinching...the gun is extremely soft shooting (softer than my model 94 30-30), plus I was shooting off bags and had a heavy coat on so the recoil was barely felt.

The plan is to clean the gun and take it back to the range and fire a 3 shot group again and see what happens, I don't understand why the group opens up so much after the first 5 shots or so, even when I let the barrel cool way down.

Sorry for the long post, I just wanted to be as thorough as possible.
 

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Discussion Starter · #2 ·
I figure I should also mention that the scope on there is a Leupold VX-II 2-7. The scope is old but appears to be in great shape.
 

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I have the same rifle and a similar Leupold scope. Mine only shoots well with 180 gr PSP core-locs. Can't explain your problem. You may want to check with an experienced gunsmith if you can find one that has time to talk this time of year.
 

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Check to see if all screws are tight on the scope mount and rings. It sounds to me like either the scope is moving in the mount or the reticle in the scope is loose.
 

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Make sure you're resting the gun on the stock when shooting.....not the barrel.
 

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How is the gun shooting with the iron sights? My dad had the same problem in the past and for what ever reason the gun was always dead on with iron sights, but accuracy with the scope would waunder. We tried two different scopes (bushnell and Leopold) over 4 years to figure out that the gun did not like the over/under style of scope mounts. We just use the gun now with iron sights. Good luck to you.
 

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I have been going through a load of BS with my 7400, I assume that is very much like a 740? I would look hard at the way the bolt is seating on the round. I don't know much about these, but I am learning. One thing I have noticed is how lousy that mechanism seats prior to the shot. Are you loading one cartridge at a time? Maybe try that?
 

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I have the same gun only 742 in 30-06. I found that once the barrel heats up it takes a while to cool off ( longer than 20 min). Mine shoots real good while cool but when hot the group opens up. I also use 180 gr Core-Lokt. Loosen the front forend screw and retighten making sure the forend does not make contact on either side with the barrel. Also put blue loctite on all the scope mount screws. Also look for wear inside the muzzle on the first one inch of muzzle. Semi autos and pumps are usually cleaned from the muzzle end because a rod can't be used from the breach end. The rubbing of the rod against the barrel rifling will wear the rifling at the end of the barrel. This will affect accuracy. A gunsmith can check for the wear and remove the first 1/2 to 1 inch of barrel.
 

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Discussion Starter · #9 ·
Check to see if all screws are tight on the scope mount and rings. It sounds to me like either the scope is moving in the mount or the reticle in the scope is loose.
Will check those tonight. I have an in-lb tq wrench, any idea where they should be as far as torque?

Make sure you're resting the gun on the stock when shooting.....not the barrel.
Always.

How is the gun shooting with the iron sights? My dad had the same problem in the past and for what ever reason the gun was always dead on with iron sights, but accuracy with the scope would waunder. We tried two different scopes (bushnell and Leopold) over 4 years to figure out that the gun did not like the over/under style of scope mounts. We just use the gun now with iron sights. Good luck to you.
Haven't really shot it with the iron sights, honestly have no desire to. I did use the iron sights to make sure the scope was hitting approx the same place.

I have been going through a load of BS with my 7400, I assume that is very much like a 740? I would look hard at the way the bolt is seating on the round. I don't know much about these, but I am learning. One thing I have noticed is how lousy that mechanism seats prior to the shot. Are you loading one cartridge at a time? Maybe try that?
The 740 is a predecessor to the 7400. I don't think that is the problem. The problem didn't really start occurring until my cousin had the new mounts put on AFAIK

I have the same gun only 742 in 30-06. I found that once the barrel heats up it takes a while to cool off ( longer than 20 min). Mine shoots real good while cool but when hot the group opens up. I also use 180 gr Core-Lokt. Loosen the front forend screw and retighten making sure the forend does not make contact on either side with the barrel. Also put blue loctite on all the scope mount screws. Also look for wear inside the muzzle on the first one inch of muzzle. Semi autos and pumps are usually cleaned from the muzzle end because a rod can't be used from the breach end. The rubbing of the rod against the barrel rifling will wear the rifling at the end of the barrel. This will affect accuracy. A gunsmith can check for the wear and remove the first 1/2 to 1 inch of barrel.
On a normal day I would agree about the barrel cooling but today it was about 35* out when I was shooting and the barrel felt cold after 20 minutes. I will check the wear near the end.
 

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Discussion Starter · #10 ·
Well, shot the gun again tonight. Couldn't hold a group at all @ 100 yards. I brought the target into 25 yards, shot 3 shots with open sights and all 3 touched. At this point I'm thinking one of 3 things, the scope is moving around in the mounts, the mounts are moving around on the gun, or the reticle is moving around in the scope...or some combination of the three. At this point I think I'm going to try to swap my Bushnell from my 22 over and see if it changes anything. If it shoots straight then I guess I can narrow it down to a problem with the scope itself, if not it's most likely the mounts.
 

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i will go out on a limb here but i'll bet the screw in the front of the forearm could be loose. having several of these guns that is the first thing i check when accuracy goes away. 99% of the time thats the issue. the last time this happened i found that the little metal clip at the base of the forearm (just in front of the magazine) was broken. ordered a new one from brownells and problem was fixed. that forearm screw has to be kept tight or the groups will open up. thats my $.02 hope you get it fixed.
 

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Have a look at the spent cartridge cases. If the primers are pushing out where they are higher than the case head face, you may have a headspace issue with the rifle. If primers are pushing out, your gunsmith should be able to tell you if it's safe to continue shooting the rifle after inspection with a no-go gauge. Remington had a deal about 10 years ago where you could turn in 740's and 742's with excessive headspace and they'd give a fraction off the price of a new 7400.

I thought it was the scope on my 742 that was the culprit - I kept chasing the zero around resetting the scope but it changed from one shot group to the next. Turned out the rifle was at fault. Gunsmith checked the rifle with a no-go gauge and said to hang it on the mantle if it had sentimental value or send it back to Remington for their deal because it was "used up".

My 742 was handed down to me by my dad. He bought it used in 1982. Who knows how many rounds the previous owner/s had fed it to stretch it out, or I suppose the chamber may have been machined improperly from day 1.
 

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Discussion Starter · #13 ·
i will go out on a limb here but i'll bet the screw in the front of the forearm could be loose. having several of these guns that is the first thing i check when accuracy goes away. 99% of the time thats the issue. the last time this happened i found that the little metal clip at the base of the forearm (just in front of the magazine) was broken. ordered a new one from brownells and problem was fixed. that forearm screw has to be kept tight or the groups will open up. thats my $.02 hope you get it fixed.
One of the first things I checked, it is tight.

Have a look at the spent cartridge cases. If the primers are pushing out where they are higher than the case head face, you may have a headspace issue with the rifle. If primers are pushing out, your gunsmith should be able to tell you if it's safe to continue shooting the rifle after inspection with a no-go gauge. Remington had a deal about 10 years ago where you could turn in 740's and 742's with excessive headspace and they'd give a fraction off the price of a new 7400.

I thought it was the scope on my 742 that was the culprit - I kept chasing the zero around resetting the scope but it changed from one shot group to the next. Turned out the rifle was at fault. Gunsmith checked the rifle with a no-go gauge and said to hang it on the mantle if it had sentimental value or send it back to Remington for their deal because it was "used up".

My 742 was handed down to me by my dad. He bought it used in 1982. Who knows how many rounds the previous owner/s had fed it to stretch it out, or I suppose the chamber may have been machined improperly from day 1.
The spent cartridges look fine to me, primers look normal as far as I can tell. See the pics below.


 

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How is the gun shooting with the iron sights? My dad had the same problem in the past and for what ever reason the gun was always dead on with iron sights, but accuracy with the scope would waunder. We tried two different scopes (bushnell and Leopold) over 4 years to figure out that the gun did not like the over/under style of scope mounts. We just use the gun now with iron sights. Good luck to you. (Mylo)

You need to do this as it will help you troubleshoot (parden the pun) the true problem I understand that you do not want to keep shooting it with only iron sights but you need to do this as a step in finding the problem. It could be the scope/mount as you suspect or it could be something more insidious. The post talking about suddenly finding your rifle with to much headspace (although I don't believe this to be true of your rifle,yet) has some merit. The barrel could be comeing loose from the reciever. It might be an inpercieveable amount(not something you can feel) but it will affect the critical alignment of the reciever and barrel. (as the scope mount is mounted on the reciever it will come across as poor accuracy with the scope and not the ironsights which are mounted on the barrel) These guns were kind of known for this. That is why they make cantilevered barrels for modern shotguns.;) You might also want to consider a one piece mount for the reciever. More rigid=less movement.

It is also the reason I shoot only bolt guns.

BTW: Gunsmiths love these guns the keep them in business was over to my local gunny yesterday and saw two brought in in the short time I was there.
 

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Discussion Starter · #15 ·
How is the gun shooting with the iron sights? My dad had the same problem in the past and for what ever reason the gun was always dead on with iron sights, but accuracy with the scope would waunder. We tried two different scopes (bushnell and Leopold) over 4 years to figure out that the gun did not like the over/under style of scope mounts. We just use the gun now with iron sights. Good luck to you. (Mylo)

You need to do this as it will help you troubleshoot (parden the pun) the true problem I understand that you do not want to keep shooting it with only iron sights but you need to do this as a step in finding the problem. It could be the scope/mount as you suspect or it could be something more insidious. The post talking about suddenly finding your rifle with to much headspace (although I don't believe this to be true of your rifle,yet) has some merit. The barrel could be comeing loose from the reciever. It might be an inpercieveable amount(not something you can feel) but it will affect the critical alignment of the reciever and barrel. (as the scope mount is mounted on the reciever it will come across as poor accuracy with the scope and not the ironsights which are mounted on the barrel) These guns were kind of known for this. That is why they make cantilevered barrels for modern shotguns.;) You might also want to consider a one piece mount for the reciever. More rigid=less movement.

It is also the reason I shoot only bolt guns.

BTW: Gunsmiths love these guns the keep them in business was over to my local gunny yesterday and saw two brought in in the short time I was there.
I can group 3-4 shots about an inch at 25 yards with open sights. I was going to head to the range today to try swapping scopes and see if that helped but didn't end up getting out this morning, might end up waiting until saturday now.
 

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The pics of the case heads / primers you posted look A-OK. The primers on my rifle were pushing out about .030-0.040" (about 1mm).

Another possiblity for your aggrivation may be the scope itself. My brother purchased a new Leupold 3-9x for his new 7400 a few years ago and he had problems with the rifle grouping consistently on zero. He chased his issue for about a year before he pulled the scope and sent it back to Leupold. Not sure what they did but after he reinstalled the scope they returned to him, the rifle shot fine.

Swapping scopes and seeing what you get with different optics may be a step in the right direction to figuring out your rifle's issue.
 

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I have an in-lb tq wrench, any idea where they should be as far as torque?
30 inch pounds for the bases and twenty inch pounds for the rings.
 

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Guess I am echoing other, see through mounts have not worked on several 7400's that have showed up on the range, mine loves 165grain bullets, does ok with 150's but poor with 180's.
I get three shots max before it starts to spray bullets all over, at least 20 minutes too cool and I like to clean a barrel between every 10 shots, after all, these are hunting guns not competition weapons made to shoot all day hot or cold.
I've tried to put in a picture of a typical 100 yard target, so far it is not working but will try and send a email with what works in my weapon.
 
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