Vertical stringing handi

[cptmclark]

I think I have exausted Handi101 and the FAQs, as well as several helpful suggestions.  I have been enjoying  fussing with my rifle, ammo, manufacturer, re-chamberer, etc for over a year now.  I think I'm close but have run out of ideas.  I now have a perfect fit for me handi in 445 Supermag (rechambered from 44 mag), several handloads that provide very good velocity and SDs, and proven sound scope and mounts.  Latching problems fixed, and function 100%.  Too much fun.
                                         Accuracy is dismal, but interesting. All group problems with all loads are vertical stringing.  There is a real group, but with some thrown well out vertically.  Some loads are staying within 1 moa wide.  Problem is they string vertically, averaging maybe 6 moa.  A problem this specific should have a simple fix, no?  All I know to do with this single shot for vertical stringing is float the forearm and shoot it properly.  Not working.  Forearm is now relieved to touch only at the screw lug (no side pressure) and at the junction with the reciever.  I pay attention to the torque on the screw, but don't measure it. I've tried different bag techniqes, mostly shooting with front bag under rear portion of forearm.  I try pulling down on forearm, and also putting hand between bag and forearm.  Not talking about a search for match accuracy here.  Consistant 2 moa would be dandy for me.
                                        One unusual component is that the chamber throat is very long.  I can't reach the lands with enough bullet in the case to be reasonable.  I don't see the long leade as causing only vertical dispersion, though.  Of course I don't know and am rank ameteur at single shots, and so I'd be grateful for your ideas, solutions, or magic fixes.  I really really like this rifle or would have given up long ago.  BTW, it's had a hundred or so rounds through it.
                                       Best load may be the Speer 240 GDSP with 32.5 H110 at 2240 fps.  Another promising bullet is the 260 Hornady, but groups always have vertical flyers. 
Thanks a bunch for any help.

[Ditchdigger]

The 445 mag that I had,liked the 265 gr.Hornady's and 296 powder. I can't remember the load,but it chrono'ed 2166 avg. The bore's on the older models were oversized,and it took nearly max load to get them shooting good.You've probably noticed by now that most of the chambers are also oversized (about .006") and the cartridge will fit very loose if fullength resized. The 300 gr.Hornady XTP will also shoot very well in most of the 445 supermag. Several guy's here on the forum,passed a reamer around and there's probably 10 or 12 supermag around. Expect 1975 fps.out of the 300 gr. hornady.and good accurcy. Some rifle maker should chamber a semi auto in this caliber for the hog and whitetail hunters out there.Its very low in the recoil department compared to the 444 and 45 70 and gives up very little to the 444 in the way of handloading.   Digger

[krod47nw]

Have you tried it without the forearm?   You didn't mention how many shots in your group.  is there a pattern to the vertical stringing, such as the first or last rounds in a group string out, or do they start low and go high, or high to low, or just random?  Also, have you checked your scope mounting?

Kevin

[cwlongshot]

You say you have gone thru the FAQ's. Thats good. Did they help and did you find any problems after reading them?

In my experience, vertical stringing is caused by three things.

 1) For-end problems.  2) Latch problems. 3) Scope moving in the mounts/internally.

 You say you have addressed the for-end, good. Keeping the for-end resting near the hinge is usually best. Also keep it soft, as it can "recoil" off a hard rest causing accuracy problems too. As long as you confident this is not the issue, try the latch ideas...
 
Time to be sure the latch is CLEAN and oil free. Then check to be cure it has consistent, even engagement. I like to use dykem, but magic marker works just as well. Mark the shelf on the barrel and open and close the action ans consistently as you can. Remove the barrel form the action and look closely. You should see even and consistent latch engagement. If you don't, re-read how to fit a barrel and proceed with that explanation. If this doesn't do it for you try the scope...

Lastly the scope. I would swap it out to one you know is working as it should. Also be sure your mount and rings are mounted correctly. You may need some friction paper if the scope is suspected to be moving in the rings.

 These things can be a bit of a pain, but I would be extremely surprised if your problem was not found to be one or more of them.

Good luck,
 CW

[greg916]

I had one last year(25-06) that strung vertically. When tried on a different frame it shot fine. I believe it was a problem with the transfer bar or hammer spring. Did not get it to shoot well. I got full credit on a new rifle.

[Sourdough]

All my Handis give vertical stringing if I don't cool the barrel after shots.  I never shoot more than three shots with out letting the gun cool for several minutes.  That is the only reason I have gotten vertical stringing.  And like I said all my handis do it.  2--30.06, 2--.223, 1--.243, 1--.45-70 and 1--.35 Whelen.

[Fred M]

One thing you have to make sure that your cases to not protrude beyond the face of the chamber. The case has to be flush or a thou or two below the face. If there is any thing sticking out you will get a variation of latch lock up and stringing.

My 257 Roberts  and the 6x47 needs full sizing each time I load these cases that is because of the springy action the case will grow when you fire them. The hotter you load the more they grow. We are only talking about  one or two thou. But this will put the latch in a different location each time you shoot. Not all cases will stretch the same because of the temper each case has.

All the above means that you should full length size each time you reload the case and set the shoulder back enough so your finished ammo is flush. To get that last bit of set back you need a press that will not flex. Many cheap presses flex and will not set the shoulder back.

Your shell holder may also be out of spec. it should be .125" I have some that are .1265". To overcome this problem you can place a piece of shim stock under the case head to get the proper shoulder set back. I also have a set of Redding shell holders from 2-10 thou
with which you can vary the length the case.

Use a straight edge and a flash light to check if you case is flush or whether it is too deep in the chamber. The light held under the straight edge will let you see what you are looking for. Remember
nothing can stick out.

 

[cptmclark]

Thanks for all of the suggestions.  Several of them were in the form of questions.                        I have not tried it without the forearm.  I did shoot it a while with original substantial tip pressure, and a lot more with the forearm relieved to provide no pressure except vertical pressure at the attach point.
                        I've considered the heating thing, but not drawn conclusion.  I shoot five shot groups.  I do get some good three shot groups, then four and five drop to 6 oclock and maybe 5 moa.  I can't duplicate this on command, but it has happened enough that I remember it.  With this heavy barrel, it is barely warm to the touch after three.                I have checked scope mounting, and replaced the scope.  I hold the rifle and watch the reticle move with each click.  I'm confident of this scope.                                 I have had latch problems.  The gun went back twice for this, was replaced once, and last time I fixed it myself by replacing parts from another handi.  An ear on the latch piece (I know i'm not calling it right) was broken off and making shavings.  Now it latches smartly, latch lever has a bit of play in it when latch (good) and it never unlatches on firing.  I will disassemble as suggested and inspect the latching surface.                I do full length size the cases.  Reason is the bulge at the extractor cutout.  I problby wouldn't get it aligned exactly.  Otherwise I'd try "neck" sizing.
                If the bore is oversize, will that cause stringing in only one direction?  Seems to me it would disperse in all directions.  If the bore is that oversized, I would problby just change it out. 
               Concerning these velocities you mention:..... I'm using Federal LPM match primers, and stopping when flattening gets serious.  I suspect that may be more due to soft primer than too much pressure for this rifle, but since I don't know I quit there.  One idea I have is to push the bullet faster, and maybe all I need is a harder primer.  (Rifle primers require deepening the pocket)  Some opine that just running it faster will often tighten groups with an oversize bore.  Of course since there are no other pressure signs I might just let the primers flatten all they want.  I don't know.  What say ye?

Many thanks for the ideas. 

[cptmclark]

Another question.  Sooooooooooooo many questions.  If there is a forearm problem with a Handi Rifle, what problems do they have?  Is it front pressure, or uneven lug pressure in the wood?  Maybe too much pinch pressure between lug and reciever??  I'll try it without the forearm, but I'd like to know where I'm going, as I may have already addressed the common issues.  I relieved all pressure except at the lug and reciever contact, and around the lug.  I thought about putting a metal tapered washer for the lug screw and using a torque wrench, but thought  that probably would be overkill.  Maybe these need a bit of upward pressure at the forearm tip?   Also while I'm here, has someone found some small pistol mag primers to be harder than others?
Many thanks,


Mike

[krod47nw]

If you can shoot a tight 3 shot group, then 4 and 5 string in the same direction, I would suspect barrel heating before anything.  As far as the forearm goes, if it shoots good without it, you may have to relieve the pressure between the forearm and reciever.

Kevin

[garandsrus]

I had a .243 Handi that would also shoot 1 MOA wide and 6-8 MOA tall at 100 yds.  The problem was that the barrel was not properly fitted to the frame (by the factory as this was originally purchased in .243).  With the action closed, I could see light between the top of the barrel and the frame.

The factory corrected the fit problem under warranty, but I haven't had time to shoot the .243 much to verify that the problem is gone.

John

[safetysheriff]

just for the fun of it, if you're willing to waste a few pieces of brass:  try using a rifle primer with your load if you're sticking with those relatively-light 240 and 260 grain bullets.   vertical stringing is often an 'ignition' problem; and can be helped with a stronger primer, a heavier bullet, a firmer crimp, and in your case pieces of brass that have a large-rifle primer-pocket uniformer run through them.   

because rifle primers require a deeper pocket the brass will only be good for rifle-sized primers after you try my suggestion of using a rifle-primer-pocket reamer.  but it may be worth it to achieve the better accuracy and the better velocity that i think you should be getting.

i definitely agree with the front bag being under the rear portion of the forearm, just ahead of the frame.

please take a look at www.6mmbr for an article by 'speedy gonzales' (i believe) on problems with 'vertical'.   a lot of things can come into play with this problem.

take care,

ss'