710 Benjamin needing help.

[11B40]

Hello all, I've been building and fixing firearms for years. Yet this is a new one for me, and I'm always up for a challenge. My good friend bought an air gun at a garage sale for $10. Since he knows I like bring things back to life he dropped it off. I have to admit I'm afraid to start taking it down til I get more info on it. Here is both what I think it is and what it is not doing.
Pretty sure it is a 710 Benjamin
Brass barrel and tube
The first problem was when I removed the screw holding the stock, the stock slipped off as did half of a soldered piece of brass holding the trigger. This I don't know if it was original but sure the 8/32 Phillips screw holding the other piece on wasn't. The trigger pin had shoulders on it for the spring and looks like you can't just drive the pin out. I re-soldered the pieces together and the trigger works. And thats where I'll stop til I hear what to do.
It pumps and holds air, cock and air will be released on a trigger pull.
What it doesn't do is fire a BB. When he dropped it off it had three BBs in it and I used the micrometer and they measured .170. I thought they should be .177? The one closest to the barrel did have a rusty side.
Safety is missing, with a good pic and measurements I could make one.
The pump handle tends to hang down a bit at times?
I really would like to fix this that is actually older than I. Thanks Much

 

[bbv13]

That's a rare old Benjamin pumper! I have to say this is the first time I have seen one. You should call Dennis Baker at Baker Airguns Monday. He's going to be your best chance to find a reseal kit, tool to take the valve a part and other parts you may need to complete the job. It needs to be completely torn down and thoroughly cleaned and resealed. There's a YouTube video about tearing down a Benjamin 312 you can look up that may help some but the 710 is a different gun. I don't think you will be able to find many people that have worked on one? Dennis is your best bet.

I'm sure some other guys will chime in soon. Maybe they will know more about it?

Bryan

[11B40]

That's a rare old Benjamin pumper! I have to say this is the first time I have seen one. You should call Dennis Baker at Baker Airguns Monday. He's going to be your best chance to find a reseal kit, tool to take the valve a part and other parts you may need to complete the job. It needs to be completely torn down and thoroughly cleaned and resealed. There's a YouTube video about tearing down a Benjamin 312 you can look up that may help some but the 710 is a different gun. I don't think you will be able to find many people that have worked on one? Dennis is your best bet.

I'm sure some other guys will chime in soon. Maybe they will know more about it?

Bryan

Thanks for the lead Bryan. Spoke to Dennis this morning and he gave me some good advice on what to look for in the feeding issue. He also said the seal kit is the same as a 310 and told me about the tool which I would buy.
Thanks again for responding
Wayne

[Rob112o]

You need a lever spring to solve the forearm from swinging down. If you put a pump of air in it, it will also keep the forearm in place. You should be leaving it with a pump in anyway. If you come back to the gun and the arm is swinging again it's got a slow leak in the valve. Probably don't need 10 of them, but this is what they look like:
http://m.ebay.com/itm/10-new-pump-lever-springs-for-Benjamin-air-rifles-310-312-317-342-347-710-/161762311300?_trkparms=aid%253D222007%2526algo%253DSIC.MBE%2526ao%253D1%2526asc%253D20150519202348%2526meid%253D03f273a27f224e6096f58a3783a981c1%2526pid%253D100408%2526rk%253D1%2526rkt%253D25%2526sd%253D111659605278&_trksid=p2056116.c100408.m2460
Think they can be simply made with a piece of metal, wire coat hangar.

Is there a bb stuck in the barrel? Get a long piece of plastic or thin wooden dowel and slide it down the barrel. If all is clear is it shooting air out of the muzzle when u shoot?

[bbv13]

I'm glad you got in touch with him. I'm on vacation and was thinking today is Saturday. It's all good because now I have another day of doing nothing.

Bryan

[11B40]

You need a lever spring to solve the forearm from swinging down. If you put a pump of air in it, it will also keep the forearm in place. You should be leaving it with a pump in anyway. If you come back to the gun and the arm is swinging again it's got a slow leak in the valve. Probably don't need 10 of them, but this is what they look like:
ebay listing
Think they can be simply made with a piece of metal, wire coat hangar.

Is there a bb stuck in the barrel? Get a long piece of plastic or thin wooden dowel and slide it down the barrel. If all is clear is it shooting air out of the muzzle when u shoot?

Thanks Rob, it seems to hold some pressure over night. The lever springs I saw on ebay but I had to speak with my buddy today if he wanted me to spend alittle on this beauty. He said go so apart it comes and parts get ordered. I did run one of my TIG aluminum filler wires down and it was clear. I also noticed right off it shoots a spray of oil with a trigger pull, I had sprayed some down the bore thinking it might have been a stuck bb or someone tried a lead shot. Today when my buddy was by I gave it a few pumps, dropped a bb down the bore and put it through a piece of 3/8 sheet rock.

[bstaley]

Interesting.....I didn't realize the 710 had an extra reservoir, for multiple shots between pumping sessions..

[Rob112o]

Congrats you got it shooting! But, what exactly are u spraying into ur rifle?

[11B40]

Congrats you got it shooting! But, what exactly are u spraying into ur rifle?

I have been home brewing my gun oil for years. I usually mix a gallon in a wine jug, and all my skeet shooting friends stop by to fill up their containers with it. Basically it's "Ed's Red" formula with another rain repelling ingredient added. We shoot in the rain and snow with salt spray thrown in at times.

[11B40]

After speaking to Dennis Baker I dove in, slowly, to take it down. So little info on the feed system is around I just thought of the mechanics involved. Pretty sure I found the issue. It seems the 710 shoots only steel BBs, what I found when I got a little deeper was what looks like a .177 lead pellet crushed in the feed system. It still isn't fixed as there is another chuck of lead pounded in even deeper. Since the feed tunnel is brass I have to go slow. This afternoon and tomorrow is out working on it as I have to mill a disco cut for my son's 1911 target pistol. Reports to follow.

[11B40]

Final update for this thread. Removed all the pellet lead from the feed channel. Tested the detent that holds a single bb so the bolt can close. All good so I reassembled and it is functioning perfectly. The 710 is only made for steel BBs. So my buddy picked it up and I think for his $10 investment he did good. I told him if I ever get the right measurements for the safety I would make one for him.
Thanks again all
Wayne

[mrcommem]

The 710 is a nice old gun that was made starting in the early 40's before the war and last made around 1946.  So your gun is around 75 years old.  I have several 710's and they are a little strange.  It is a multi-shot repeater with an onboard pump.  It has an external reserve tank just above the trigger in the stock.  This gun can be pumped 15 times or more and will shoot several hard shots-around 700 for the first and decreasing with each shoot.  A pump or two will restore top velocity.  710's are made to shoot only steel shot-no lead as it is to soft the make it thought the loading mechanism.  I have chronographed the velocity at around 750 fps!!  A great find for $10.