Author Topic: .223 accuracy (Read 1128 times)

netcott · « **on:** September 19, 2006, 08:06:22 AM »

I am having some consistency problems in .223 bull barrel rifle. Whats going on is that I will get 2-3 consecitive shots that will place in well under a half inch group and then the next couple shots will also shoot in under a half inch group, except that group will be about an inch from the first group. So if I shoot 5 shots in a row I will get 3 touching and the other two touching. This happens with both the american eagle ammo I have been shooting and also my handloads. I have rtv free floated the forend and I have tried shooting resting on the reciever and the forend. (accuracy does seem better off of the reciever). I Tried two scopes with the same results. I have made sure that there is no oil on the lockup mechanism.

Has any one ever had a similiar experience? Any ideas on what to try? I have been to the range every weekend for a month with the same results.

quickdtoo · « **Reply #1 on:** September 19, 2006, 08:39:52 AM »

Try some oil on the latch, it may or may not help, depends on the latch engagement, see the barrel fitting info in the FAQ on how to check latch engagement. Double check to make sure the barrel isn't touching the forend when it warms a little.

Tim

Paul5388 · « **Reply #2 on:** September 20, 2006, 03:07:22 PM »

Try removing the RTV. That's actually putting a load between the barrel and the forearm (i.e. upward tension). Some Handis shoot good that way and some don't. It looks like yours doesn't. It might be the squish RTV has that's changing too (squish is a technical term denoting a degree of mushiness

).

Of course, just getting rid of the RTV isn't going to float the barrel, so you might check and see if there is clearance between the barrel and forearm with the RTV removed. Shoot it that way and if it isn't better, try actually floating the barrel by removing material in the barrel channel of the forearm. Sometimes it's easier to use a couple of 1/4" flat washers (they can't be over 5/16" OD and still fit in the forearm recess for the lug) between the lug and the forearm. Get some clearance and there probably won't be anymore movement of POI (Point of Impact). The barrel heating and making contact with the forearm is probably changing the POI.

netcott · « **Reply #3 on:** September 21, 2006, 11:51:25 AM »

Before I did the rtv in the forend I was having trouble getting groups less then 3". I pulled the forend off and was resting the barrel on the stud that the forend sits on and was able to get sub moa groups. I since have not been able to reproduce those groups with or without the forend and the only other things that I did, other than the rtv was that I filed the locking lug so that the gun would stop popping open and I removed all oil from the locking mechanism.
I am going to try shooting this weekend with the locking mechanism reoiled.

quickdtoo · « **Reply #4 on:** September 21, 2006, 11:57:37 AM »

Smoke the latch shelf and see what kind of engagement you're getting, it should be even all the way across.

Tim

Paul5388 · « **Reply #5 on:** September 21, 2006, 12:16:16 PM »

Obviously the RTV didn't help, but you know the gun will shoot sub-MOA without the forearm. That indicates the forearm is the problem, not the locking shelf. If the forearm is properly floated, it should be almost like when you shot it without a forearm installed.

quickdtoo · « **Reply #6 on:** September 21, 2006, 01:55:41 PM »

Quote from: netcott on September 21, 2006, 11:51:25 AM

I since have not been able to reproduce those groups with or without the forend and the only other things that I did, other than the rtv was that I filed the locking lug so that the gun would stop popping open and I removed all oil from the locking mechanism.

It seems to me that you might have filed the latch shelf a little too much on one side or it was uneven to begin with, that will cause inconsistent lockup and poor accuracy. I'd definately check the latch engagement before you do anything with the forend.

Make one change at a time, then if it doesn't work, then you know what you need to do next. Making multiple changes without shooting between changes can be frustrating.

Tim

Paul5388 · « **Reply #7 on:** September 21, 2006, 02:12:26 PM »

OK Tim, I'll concede!

The first thing to do is check the shelf, if it's OK, put some oil back on the shelf and shoot it. I don't see how the shelf being filed untrue is going to make it shoot bad groups, but I can see how the lack of oil could affect it.

quickdtoo · « **Reply #8 on:** September 21, 2006, 02:23:08 PM »

Fred explained why even latch engagement is important at some time or another, don't recollect whether it's on his web site or in a post, but I've had several barrels that showed heavy engagement on one side to very light engagement on the other side, they didn't shoot well until I honed them to hit evenly across the latch shelf.

Tim

Paul5388 · « **Reply #9 on:** September 21, 2006, 02:32:17 PM »

Tim,

I would think that was a simple mechanical connection that would remain pretty consistant. It isn't like the angle to the shelf can move, so I don't see how that's going to make the gun shoot badly. OTOH, an unoiled shelf could change lockup with the degree of force used to close the action, which in effect would change the headspacing if more or less cartridge is allowed room to move.

quickdtoo · « **Reply #10 on:** September 21, 2006, 02:47:11 PM »

I'll leave the technical explanantion to Fred, but with the soft material the shelf is made of, even latch engagement makes sense to me, oiled or not.

Tim

Paul5388 · « **Reply #11 on:** September 21, 2006, 02:59:35 PM »

Sure, there should be even latch engagement all the way across at a right angle to the bore, but that should just make a shift to one side, if at all, whereas the degree of latch engagement, i.e. how much the latch engages, will affect headspace.

quickdtoo · « **Reply #12 on:** September 21, 2006, 03:09:23 PM »

Paul,

Umm, I think you just said the same thing I said, only in different words.

Fred states that a .001" movement of the latch at firing can create a 1" change in POI at 100yds. If latch engagement is heavy on one side and light to no contact on the other, there could be at least that much movement and considerably more depending on headspace, right?

Tim

Paul5388 · « **Reply #13 on:** September 21, 2006, 03:51:21 PM »

You would think the lack of support under one side would let the breech torque to that side, but I would think it would be a consistant torque, since it's a mechanical connection or lack of connection.

The other is going to give greater inconsistancy that will depend on the amount of force used to close the action and how consistant that force is applied everytime the action is closed. There has to be enough force to overcome the friction from a dry shelf and it's there sometimes and sometimes maybe not.

I'm fixing to send you a pm on my email notification I just messed up!

netcott · « **Reply #14 on:** September 21, 2006, 04:33:55 PM »

As I mentioned in a previous post I tried shooting without the forend since I had applied the rtv and was not able to reproduce the sub moa groups. I wish I had a digital camera so I could show you the groups. I am literally getting 2-3 group strings where the bullets are touching each other before the poi shifts to another location. Whatever the problem is, it seems to be consistent for a couple shots before it changes.

I will check the latch eveness, and I am going to try shooting this weekend with the oil on the latch.

Ditchdigger · « **Reply #15 on:** September 21, 2006, 05:07:09 PM »

If you've got enough ammo left after you try the oil on the latch,try puting a bussines card in front and back of the mounting lug of the forend.Put just enough of the cards to float the barrel and it should help. Digger

Paul5388 · « **Reply #16 on:** September 21, 2006, 05:10:22 PM »

Let us know how it works out!

netcott · « **Reply #17 on:** September 22, 2006, 05:33:21 AM »

I smoked the latch and it was hitting all on one side. I did some work to it and was able to get it more evened in the center. Now of course if it does shot good we won't know if it was oiling the latch or the latch engagement. I hope I can get this figured out because from what I see the barrel will shoot, it's just a matter getting the rest of the gun consistent.

Paul5388 · « **Reply #18 on:** September 22, 2006, 06:10:50 AM »

The object is to get the barrel to shoot right. It doesn't really matter if it's the oil or the shelf, if whatever it is gets you up and running!

quickdtoo · « **Reply #19 on:** September 22, 2006, 06:23:58 AM »

As so many of us have found out, whatever works!!

There's no one set of conditions for which all Handis will shoot good under, each rifle is an individual and what works for one may not work for another. The O-ring trick is a perfect example of this, I have a bunch of Handis, some shoot better with it and that's all I needed to do, but the majority of them it didn't help, made them shoot worse.

Tim

E Rex B · « **Reply #20 on:** September 22, 2006, 07:52:32 AM »

I was at the point of throwing my Handi in the dumpster but it is shooting now. Take a strip of emery cloth, put it on top of your barrel and FIT THE SCOPE BASE TO THE BARREL. Then GLUE IT DOWN.
Rex

quickdtoo · « **Reply #21 on:** September 22, 2006, 08:16:42 AM »

Scope rail fitting tips are in the FAQ and Help sticky, there's more to a good fit than just lapping the rail.

Tim