G-W....Here is how I got my Gibbs to shoot much better. I also use a postell style bullet...530 gr.....cast at first at 30:1...and lubed with alox. when I experimented with a harder alloy [24:1] groups tightened up. I am going to try 20:1 when I get a chance. I also size the bullet to be no more than .001 under bore diameter. [My bore is a true .451] The bullet drops out of the mould at .450 and is sized/lubed in a .450 die. Try shooting without a wad. My rifle at least shoots better without one. The next thing I did was buy the Shaver -Gibbs rear tang sight from Buffalo Arms.  The pedersoli sight was "adequate" but I found that a better sight made for better groups. The next thing I did was check the fit of the forearm to the barrel by using inletting black. I found that the forearm tip was actually pushing up on the barrel. I shaved off the high spots with a barrel inletting tool so there was no barrel contact foreward of the barrel key. I then glass bedded the barrel from the key to the breech. I believe glass bedding is not allowed in some matches....David will know which ones i'm sure. Check for nipple erosion. I'm told even the platinum nipple holes will enlarge over time even though mine hasn't even enlarged by a thousandth yet. Lastly, I thinned the trigger spring a little and polished the sear contact surfaces to lighten the trigger pull. Please make note of the fact that I did not remove metal from the surfaces to change the sear angle! I only polished the surfaces. When I first got my Gibbs it definately showed promise. All told it took 2 years of experimenting to iron out the bugs. Right now my Gibbs will shoot 10 shot groups of  2 minutes of angle at 200 yards if the wind cooperates and I don't do anything stupid.  Hope this helps.   cheers   Paul

Gellot. It sounds like the same problem I had with mine and several others I've heard of. It may be due to the hook wearing in the breach. To check it you need to mount the barrel verticaly in a vice. Take the breech off the stock and fit it to the hook. If there is movement around the square and or you can get feeler gauges into the gap between the breech and hook then thats where your problem is. You cannot check this properly without taking the breech off and re bedding the barrel will not fix this although it might help for a few shoots. A lot of this has been caused by inadequate case hardening.

Thanks Mike....taking the breech off and checking that would seem straight forward enough, it also makes sense.

If I do discover that there is play there I assume that the fix would be to get the two surfaces flat with each other?  Am I right in thinking that some very careful file work and polishing will be in order? 




Thanks David.

If glass bedding is not allowed, is any type of bedding allowed as long as it's not of a modern type...would packing the thing with paper or strips of shim be permitted?

G-W....Very interesting stuff!  Two possible solutions. When reassembling the barrel to the breech, could a small piece of steel "shim stock" be slid into the sloppy area to make the barrel/breech fit tight? Maybe you could have a very small spot weld done on the sloppy side of the hook, then file and try, file and try etc. until you have a perfect fit. I built a Rigby rifle from parts and getting a good fit of the hook to the breech was way harder than I expected since the hook literally disappears into the breech. It was hard to tell exactly where it was binding and where to file. I still relieved the wood in the forearm foreward of the key and glass bedded from the key to the breech. It locks up like a bank vault when I put in the key. The Rigby will be in a deer blind with me this Sunday!    cheers      Paul

I must admit that idea had crossed my mind...not welding but somehow fastening it together so it can't move.  But as you say...not sure if that is permitted? 

It might get to that Paul.

After thinking that I'd sorted out the breech...stopping the movement tests ware a little less pleasing than I'd expected.  It also seems to have a tight spot down the left-hand side of the barrel.

This rifle is nearly always shot at 100M, I was figuring on getting it working well at that distance before moving further out.

I hear what you say about bad juju/karma...I'm not quick to blame the tool, unless it's myself. 

My average at 100M last year with the BPCR was 96 so I was pretty pleased...but it was only 89 with the Gibbs.  The last match of the year was a 100M/200M affair and I thought I'd sussed it with a 96/94!  The weekend after I took it to the range with the same load, same batch of bullets and struggled to break 85.   


I'm now getting ready to dust it off and start in again this year...all sorts of ideas to try out...now where's my soldering gear at.   

No Mike, not done that at all, I just got it to fit as closely as possible..not tried soldering it or anything close to that yet...I'm not that brave.

My next step is going to be to look at the tight spot on the barrel.

We have been shooting the Gibbs out to 1000 yards, and have found that the hook breech has to be tight.  You can tap the hook with a ball peen hammer to swell it  and then stone the high spots until the fit is tight.
   Kenn

justmike wrote on Jan 27^th, 2010 at 8:39pm:



No, it's pretty tight.

Any news on this GW