Switching Barrels/Accuracy?

[J A XSP]

I tend to want to leave a good-shooting Contender rig alone once I get some loads dialed in, especially if I'm likely to hunt with it. Sometimes though, it's necessary for multiple barrels to share a frame.

I'm wondering what sort of experiences everyone has in terms of repeatable accuracy across loads and consistency of POI after removing a barrel and putting it back on the frame. Any particular barrel/frame combo that seems finicky? Any barrels or chamberings that seem particularly consistent?

Do you tend to leave frames and barrels permanently set up or switch around pretty often? Lots of barrels that share one frame? A particular frame that's only used for a couple of barrels?

Inquiring minds want to know. :D :D

[Bobby Tomek]

Years ago, I used to swap around barrels quite a bit, but I'm down to just a few and tend to leave them set. I did some experimenting back then, and while a few tend to think of them as snake oil or a gimmick, I found that using hinge pins that minimize slop help return the POI to an acceptable level -- usually well within an inch at 100 yards of where it was previously.

No, all frame/barrels combos don't need them. And those who use brute force to hammer a pin into a frame are doing more harm than good. But used as intended and with a dedicated forend that is always tightened the same, those pins and the resulting solid lock-up do make a difference and remove much of the guesswork when swapping around barrels.

Switching buttstocks tends to create the greatest shift.

[J A XSP]

Years ago, I used to swap around barrels quite a bit, but I'm down to just a few and tend to leave them set. I did some experimenting back then, and while a few tend to think of them as snake oil or a gimmick, I found that using hinge pins that minimize slop help return the POI to an acceptable level -- usually well within an inch at 100 yards of where it was previously.

No, all frame/barrels combos don't need them. And those who use brute force to hammer a pin into a frame are doing more harm than good. But used as intended and with a dedicated forend that is always tightened the same, those pins and the resulting solid lock-up do make a difference and remove much of the guesswork when swapping around barrels.

Switching buttstocks tends to create the greatest shift.

I agree about the "oversize" pins. I have 2 or 3 around and try to match a frame and barrel to a pin that's pretty tight. I've definitely seen groups tighten up when going from a relatively loose pin to one that takes just a little bit of persuasion . For the barrels that I'm switching, especially for casual shooting or barrel testing where I might change out at the range, I want a pin that pushes in and out without too much fuss. I have noticed that when I need to remove and reinstall a barrel in a frame with an oversized pin, it tends to be very consistent in terms of returning to POI and maintaining accuracy

It's interesting about the stock...if the bolt isn't torqued down good and tight, things get pretty inconsistent. That's not necessarily intuitive but it makes a difference. As for the forends, the only way I feel satisfied the they're really locked in place is either the hanger system or pillar bedded.

[BT]

I don’t swap barrels around much anymore either and like to keep my setups together once I’m really pleased. I agree with the oversized pins, though I’ve only needed them on a rare occasion. I’ve been through alot of barrels over the years and have really reduced the number that I have now. Most of the time POI has not moved much, if any, but a grip and forend change has shown the biggest results for me as well. Most recently I had a GA Jim laminated set on a G2 and swapped them out for a Pachmayr set, resulting in my group moving 3” to the left and the same upward. I’ve never taken for granted that the POI will be right where it was prior to swapping anything around and always confirm where it’s at prior to hunting.

[BobT]

I'm currently on a mission to have a frame dedicated to each barrel, that said I have never noticed a difference in the raw accuracy of a particular barrel when it was switched from one frame to another if everything else remained the same. A point of impact shift has been the norm for me though and as Chris mentioned, a zero verification is a must!

[atmtc]

Anymore, I just use two frames. One for pistol & one for carbine bbls. I stick with the same forends & have had no problem w/POI shift.

[Mjshell]

I rarely switch barrels. I get them set up and leave them alone. Now with that being said, I did change a frame / barrel/ wood combination up last week. It shifted point of impact 6” or so. I’m surmising it was more due to the different forend than the frame/ barrel switch.

[J A XSP]

Anymore, I just use two frames. One for pistol & one for carbine bbls. I stick with the same forends & have had no problem w/POI shift.

That's interesting to note...I wonder if keeping the forend with the barrel and trying it on different frames would show any effect.

I've been comparing a couple of 44 mag barrels recently and switching them out using the same frame and stock set. Seems like they've held fairly well but I haven't really checked to see how close they stay. I'm thinking that a torque screwdriver is in order. :)

[atmtc]

"That's interesting to note...I wonder if keeping the forend with the barrel and trying it on different frames would show any effect."

I haven't tried it, but I'm guessing that it would, due to the change in headspace if for no other reason. I'll bet your .44 Mag bbls (or any other case that headspaces on the rim) would probably not change a great deal.

[J A XSP]

"That's interesting to note...I wonder if keeping the forend with the barrel and trying it on different frames would show any effect."

I haven't tried it, but I'm guessing that it would, due to the change in headspace if for no other reason. I'll bet your .44 Mag bbls (or any other case that headspaces on the rim) would probably not change a great deal.

I'll have an opportunity to check that out...I've had my 25-45 barrel on a Contender frame, set up as a pistol with my wide target forend on it. I'm (finally) getting a new SSK frame and that barrel is destined to live on it. I've got a pic of the last target I shot with it, testing some loads. I'll duplicate those loads, or at least the best of them, and try them with the new frame. I'll know right away whether the POI suffers a big shift or whether the loads that showed the best accuracy with the older frame are also accurate with the new one. :)

[atmtc]

I'm waiting for the results with baited breath. Also wondering how much the locking bolt/locking table interface would have to do with it. When you get right down to it, there's certainly not much holding these little guns together. From an engineering perspective I'm constantly amazed at the accuracy that we get with these things.


I'll have an opportunity to check that out...I've had my 25-45 barrel on a Contender frame, set up as a pistol with my wide target forend on it. I'm (finally) getting a new SSK frame and that barrel is destined to live on it. I've got a pic of the last target I shot with it, testing some loads. I'll duplicate those loads, or at least the best of them, and try them with the new frame. I'll know right away whether the POI suffers a big shift or whether the loads that showed the best accuracy with the older frame are also accurate with the new one. :)

[J A XSP]

I'm waiting for the results with baited breath. Also wondering how much the locking bolt/locking table interface would have to do with it. When you get right down to it, there's certainly not much holding these little guns together. From an engineering perspective I'm constantly amazed at the accuracy that we get with these things.

Headspace and consistent lockup is definitely requisite. I've had instances where I was having to slam the action a little too much to get lockup with a particular barrel and getting lousy accuracy. Same barrel on a frame that allowed for easier lockup and obviously, more consistent full engagement of the lugs and things tightened up very nicely.
It's true that design-wise, they're not particularly robust. :)

[J A XSP]

So here's a data point...I switched my 25-45 barrel on to my new SSK flatside frame and took it to the range with the same loads as I shot last session on the Contender frame. I didn't get all the way through my load ladder but the out come was very evident just with a few groups down range.

The factory rounds are touching at 50 yards and hitting essentially the same point of impact as with the other frame. The first 3 loads all showed sub-MOA (an improvement over the performance last session) and again, essentially the same point of impact that it had with the same barrel, grip and forend on the other frame.
10425

[Bobby Tomek]

Good info! And with those groups, it definitely looks like your barrel is brimming with potential.

[J A XSP]

This thing looks to be downright boring at some point. :) Those are the 100 grain HP plinker rounds I've been working on.

I haven't done any work at 100 yards yet but I expect that the same half-MOA accuracy will hold.
I've got a Leupy 2.5-8X scope on it so probably out to 200 will be pretty doable. When I get a chance to start really fine-tuning I'll have to work out that far just to be able to keep the holes from touching. :D

[BobT]

So here's a data point...I switched my 25-45 barrel on to my new SSK flatside frame and took it to the range with the same loads as I shot last session on the Contender frame. I didn't get all the way through my load ladder but the out come was very evident just with a few groups down range.

The factory rounds are touching at 50 yards and hitting essentially the same point of impact as with the other frame. The first 3 loads all showed sub-MOA (an improvement over the performance last session) and again, essentially the same point of impact that it had with the same barrel, grip and forend on the other frame.
10425

Very nice! I'll be able to test the same scenario soon, I hope. My SSK 50 now wears my .30-30 AI barrel with the same Pachmayr grip and forend that was on the old frame, I just need to remount the scope and I'll be ready to try it out.

[bsekf]

I switch barrels but always back and forth between the same barrel/frame. I carefully measure the barrel to frame distance because that is part of headspace. IMHO if you change the headspace the POI and accuracy will change. Luckily I have 2 Contender and 2 Encore frames the measure .001 with most barrels. One other Contender measures .005 but shoots fine with a dedicated barrel. I do not know if the hinge pin hole in the frame or the barrel lug is drilled wrong.