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Posted By: Tom C Modify or Sell? - 08/09/07 02:16 PM
I'm hoping to obtain some good advice on whether to modify a Renato Gamba Hunter Special I picked up in January or sell it and look for something that fits me better.

After I bought this gun I realized the stock was cast on (I'm a tall, skinny, right hander - a big rooky mistake, not having purchased many used SxSs in the past). I sent the gun in to have the stock bent to cast neutral but it still shoots high and right.

At that point I decided I better have a gun fitting done rather than spending money foolishly trying to modify the gun without knowing where it actually should be. Here's what the fitting showed me. The Gamba has the following dimensions: LOP=14 7/8", Neutral cast, DAC 1 7/16", DAH 2 7/16".

Here's what I need: LOP = 15 1/8", DAC = 1 7/16", DAH = 2 5/8" DAF = @1 3/4" @ pitch or stand = 2" @ 4 degrees. 3/8" cast off.

I would obviously like to correct the point of impact as well as a cheek slap problem I have always had with all guns.

The gentleman that did the fitting suggested selling the gun and buying one that fits better. He wasn't sure he could bend the stock enough for my needed dimensions - something about the thru bolt design.

I like the gun but I'm not married to it. So my question is - should I modify it or sell it and buy something else?

P.S. If you suggest selling it I will need your input on it's value. I can't find information on the Hunter Special model. It has engraved side plates, 27 1/2" barrels, 12 gauge, monobloc, double triggers, Anson latch on forend, pistol grip, southgate ejectors and nicely figured wood.

Thanks!
Posted By: Rocketman Re: Modify or Sell? - 08/09/07 03:01 PM
This is an economics and time issue. I'd follow the fitter's advise and not try to bend more than the wood wants to. I think you might find you can have a new stock made to your dimensions from a decent piece of wood (don't shoot for the moon on your first one out - use it to learn) for an economical price. The compeating plan will be to sell your gun and buy a different one. Compare expected extra cash outlays between the two plans. A piece of plainish wood of good quality is not expensive and basic duplication, with sufficient overage for experimentaion is not all that bad.
Posted By: Keith E. Carlson Re: Modify or Sell? - 08/09/07 03:29 PM
If you haven't done so, I would add a spacer or two to lenghten the LOP to see if that lowers your POI.
You stated that the gun shoots high and right which would seem to indicate you need to move the "rear sight",your eye, lower and to the left.
A longer LOP should lower the POI as your cheek will contact the stock further to the rear, thus lowering youe eye.
If the gun continues to shoot to the right try putting a layer or two of moleskin on the left side of the stock to move your eye to the left.
Did the gunfitter have you shoot the gun or did he simply takes some measurements? I believe most good fitters would have you shoot both for POI and at clay targets before finializing the fit.
Posted By: Buzzbee Re: Modify or Sell? - 08/09/07 03:50 PM
Originally Posted By: Tom C
The gentleman that did the fitting suggested selling the gun and buying one that fits better. He wasn't sure he could bend the stock enough for my needed dimensions - something about the thru bolt design


If the stock can't be bent to fit you and you can't hit where you aim, then whats thare to think about, the option is clear.
Posted By: Tom C Re: Modify or Sell? - 08/09/07 04:08 PM
I did not shoot the try gun. He simply took some measurements. It was kind of funny because I called him about a year ago and he wanted $350 for a fit and shoot. When I called him a month ago he said it was $100 for a fit and he did not mention shooting the try gun.

I think I will try the spacers and repattern the gun. Seems I threw away the pattern targets and can't remember for sure if it shot right or left although I am pretty sure it shot right. I'm sure it shot high.

As far a bending the stock, he said he didn't know if you could bend it that far but was willing to try. That is what make me nervous. I'm going to ask Mike Orlen about this since he did the first bend to make it cast neutral. Mike has always been very good to work with and I trust his opinion.
Posted By: builder Re: Modify or Sell? - 08/09/07 05:17 PM
I am not sure what is going on but that does not sound like a fitting that is reliable. I think Keith E. Carlson is right about what you need. By adding spacers between the pad and the butt you will move your face back and lower your eye so the gun will shoot lower. It sounds like you need cast on like a lefty to move the pattern to the left. A small amount of bending might make the gun fit well.

Try patterning at 16 yards. Mount it as if you are shooting clays. Don't mount it like you are aiming because you will either push your face down further on the stock or to the side more than if you make a fairly quick mount as if you were shooting game or clays.

Find the center of your pattern. For each inch it is off center, move the stock 1/16". So if it is 4" high move the stock comb down 4/16" (1/4"). Mike Orlen can discuss this with you to clear up any questions I am sure.
Posted By: Jent P Mitchell lll Re: Modify or Sell? - 08/09/07 05:40 PM
Hello Tom C. and Hello Milt, Tom C. , Call me and I will try to help you. To many words to type. I am 6 feet 2 inches tall and right handed. My length of pull from the front trigger is any where from 15 and 1/2 inches to 16 inches. I can probably save you a little time and aggravation. Jent. Jent's phone number is 703-855-1110.
Posted By: Tom C Re: Modify or Sell? - 08/10/07 01:18 AM
When I had the stock bent to neutral it brought the pattern closer to the aim point but not enough and it still shot high. As I mentioned, I think I should repattern the gun with an extension or spacers before I do anything although I am in the middle of a move so it may be a while before I can do that.

Jent - I'll give you a call this week. I always like talking about guns and shooting.
Posted By: mike campbell Re: Modify or Sell? - 08/10/07 02:16 AM
Originally Posted By: Tom C
I'm hoping to obtain some good advice on whether to modify a Renato Gamba Hunter Special I picked up in January or sell it and look for something that fits me better.

After I bought this gun I realized the stock was cast on (I'm a tall, skinny, right hander - a big rooky mistake, not having purchased many used SxSs in the past). I sent the gun in to have the stock bent to cast neutral but it still shoots high and right.

At that point I decided I better have a gun fitting done rather than spending money foolishly trying to modify the gun without knowing where it actually should be. Here's what the fitting showed me. The Gamba has the following dimensions: LOP=14 7/8", Neutral cast, DAC 1 7/16", DAH 2 7/16".

Here's what I need: LOP = 15 1/8", DAC = 1 7/16", DAH = 2 5/8" DAF = @1 3/4" @ pitch or stand = 2" @ 4 degrees. 3/8" cast off.

I would obviously like to correct the point of impact as well as a cheek slap problem I have always had with all guns.

The gentleman that did the fitting suggested selling the gun and buying one that fits better. He wasn't sure he could bend the stock enough for my needed dimensions - something about the thru bolt design.

I like the gun but I'm not married to it. So my question is - should I modify it or sell it and buy something else?

P.S. If you suggest selling it I will need your input on it's value. I can't find information on the Hunter Special model. It has engraved side plates, 27 1/2" barrels, 12 gauge, monobloc, double triggers, Anson latch on forend, pistol grip, southgate ejectors and nicely figured wood.

Thanks!


Tom,


This is whacky........ the numbers don't add up.

1) You're righthanded, the gun was cast on and it shot RIGHT? If it was cast on enough to matter, it should have shot LEFT for you originally. Having it bent neutral should have made it shoot MORE RIGHT, but if it's really zero cast, it shouldn't shoot right of center.

If this gun is cast ON or NEUTRAL and shoots RIGHT for you, it's possible that the issue is not gun fit, but barrel regulation. Before patterning dynamically for fit (as Builder describes)pattern it to see if it shoots to point of aim. That is, benchrest the gun like a rifle, do whatever contortions you have to get the bead dead center between the barrels, no rib visible and touching a bullseye at 6 o'clock, just like shooting a rifle. If you can't get it to shoot dead center with that sight picture, there may be an issue with regulation that you don't want to try to overcome with stock alterations.

BTW, do both barrels shoot to the same POI?

Have you actually tried shooting some targets with it?

2) For practical purposes, there's little difference between the Gamba's dimensions (LOP=14 7/8", Neutral cast, DAC 1 7/16", DAH 2 7/16") and your ideal (LOP = 15 1/8", DAC = 1 7/16", DAH = 2 5/8",3/8" cast off).

It's unlikely that 1/4" LOP will cause a significant change in POI. With an identical DAC of 1 7/16, the 3/16" difference at heel is nearly negligible BUT is in the right direction to lower the POI. I'd bet only the 3/8" cast is significant and again, if you gained that on the Gamba, your POI should move more RIGHT, apparently not what you want.

3) As to shooting HIGH, if a gun doesn't fit, shooting high is the best way to err.....you don't have to bend it, you can sand down the comb.

In any event, I'd start with a benchrest pattern.
Posted By: Chicago Re: Modify or Sell? - 08/10/07 04:02 AM
Tom C:
You may want to give Hugh Lomas Gunmakers a call - Hugh is located in Elkhart Lake, WI and can handle any issue a double ever had. He also does proper fittings at a reasonable price.
Posted By: Tom C Re: Modify or Sell? - 08/10/07 01:07 PM
To try and answer some of these questions I'm going to run out at lunch today and pattern it again just to see where it shoots for sure. Luckily, I've got a gun club about 15 minutes from my office. I have shot it once at clays and shot the lowest score I have ever shot. When I patterned it after I purchased it I was not happy with the POI and that's when I noticed the cast on. That's when I sent it to Mike O. Moving the stock helped but didn't move it far enough towards POA. I just can't remember if it was shooting high right or left because I did this in April and then forgot about it for a while until I shot it at clays.

I'll talk to you guys soon. Thanks for all the help.
Posted By: Tom C Re: Modify or Sell? - 08/10/07 06:35 PM
I was wrong. (It is hard to say!) I patterned the gun at 16 yards today. I took 5 shots from the right barrel at one target and then 5 shots at another from the left. The right barrel shoots about 4 1/2" left and 2" high. The left shots 3 1/2" left and 2" high. All 5 shots for each barrel were very consistent and it was very easy to see where the gun is shooting.

When I put an extension on of about 1/2" it dropped the pattern almost perfect. The extension was just a pad that compressed to about 1/2" thick.

So I would think that I need to add about 3/8" to 1/2" to the LOP and put about 1/4" cast off on the stock. Correct?
Posted By: Rocketman Re: Modify or Sell? - 08/10/07 07:40 PM
I'd suggest you make a shootable pad and shoot some before committing to bending or a finished pad. Pattern some more, too. BTW, patterns are much easier to keep up with if you photo them with a good digital camers - include details in print on the pattern sheet.
Posted By: builder Re: Modify or Sell? - 08/10/07 07:42 PM
Sounds right to me except you need to add 1/4" cast off to what you already have. If there is no cast at present then you are correct.

Enjoy your gun!
Posted By: Tom C Re: Modify or Sell? - 08/10/07 08:24 PM
I did take a few photos with my phone which turned out OK. If you want I will email a couple direct to you. I used graph paper made for an easel. It has 1" squares drawn on it and is about 2' x 3' so it makes evaluating your patterns simple.

The stock is cast neutral now. When I purchased it, it was cast on.

Thanks for all your help.
Posted By: KY Jon Re: Modify or Sell? - 08/10/07 10:45 PM
Add the extra pad and shoot the gun. In fact I would shoot if for several months. When it gets cold and you start wearing a heavy coat you may find that you do not need the extra pad. I tend to shoot two different guns in hot and cold weather.

Be aware that all guns do not have a point of impact that relates directly to the sight picture. Some hit high and some hit low or to one side or the other. I had a Parker that had barrels which did not converg at any reasonable range. The right barrel hit consistently about a foot too far to the left. When made the barrels were not well regulated.
Posted By: Tom C Re: Modify or Sell? - 08/12/07 03:08 PM
I am considering having it shoot slightly high in warm weather so that when I am wearing a heavy jacket in cold weather it will shot dead on. Currently it shooting 2" high at 16 yards.

As far as left or right I would like it to shot where it points for me. Both barrels are shooting high and left (3-4 inches)almost to the exact point. I have shot it a number of times and have shot trap and clays with it. In fact, I shot the lowest clays score I have ever shot with it - kind of embarassing. Based on the pattering at 16 yards I can see why I can't hit anything with it - it's very obvious.

One question I still have is "am I asking too much to have the guns I shoot the most often, shoot to approximately the same spot? If I am shooting my Rizzini O/U for clays, my Gamba for pheasants or my Stevens 5100 for grouse shouldn't they all shoot to the approx. the same spot? Don't forget I have a short memory! How will I ever remember where to hold when that grouse pops up if they all shoot differantly?
Posted By: builder Re: Modify or Sell? - 08/12/07 04:25 PM
No, it is not too much to ask and the answer is apparent to me. Send to Mike and add 1/4" cast off and that is it. During the summer use the slip on pad to lower the POI and in the winter take it off and your clothes will add the difference. Sounds like it will be to dead center for both seasons.
Posted By: builder Re: Modify or Sell? - 08/12/07 04:26 PM
No, it is not too much to ask and the answer is apparent to me. Send to Mike and add 1/4" cast off and that is it. During the summer use the slip on pad to lower the POI and in the winter take it off and your clothes will add the difference. Sounds like it will be to dead center for both seasons.

The alternative would be to add a pad that is adjustable like the Morgan but that seems more trouble and expense than it is worth. Besides, the summer pad will protect the butt end when put in a rack.
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