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Greetings Again,
Another thought. If you are getting poor accuracy with pretty much everything you have tried it is most likely a rifle problem rather than the loads. I would try a different scope in different rings (not lapped). You can check the base screws while you are at it. You don't need a flash scope for this just one of proven reliability. My next pick would be the barrel. Rechambering a 7mm SAUM to 7mm WSM sounds a bit odd. why would you do that?
Regards Grandpamac.
As I've been reading through this, yeah been here several times for other people. You are at the point where I'd suggest cuddles and hugs, a nice hot drink and a sit down in the sun haha. Pricks of things, rifles that won't group.
List of possible culprits in no particular order:
Barrel issue, muzzle damage, chamber fault, leade fault, fouling, rifling damaged through bulge or something else.
Bedding issue, pinch, movement, contact point etc
Mechanical fault, lugs not bearing properly, mount screw tensioning the bolt, something not bearing evenly, trigger or sear, something not in line or on the piss.
Scope mounting security alignment and general faults.
General prick of a rifle that just doesn't like bullets...
What would I do? Get a factory load and try that then if that won't play start with a serious going over of the rifle looking at every possible issue and eliminating each as you go. If you can't find anything, try another complete scope and mount setup with the factory load (groups not point of impact accuracy so provided its on paper you're good four rounds fouler and three). Now I'd expect by this stage that a different scope would either show a massive change or no change at all, if no change find a lead sinker of about 75gms or so and securely tape it to the barrel about 100mm or so back from the muzzle and try again. This is farking with the barrel harmonics and it will most likely either get worse or better, if no change then don't bother going further. If worse, you are at least gaining understanding of the issue, it's a harmonics issue and the barrel whip is leaving the muzzle at a different position on bullet exit from the muzzle and you need to make a serious adjustment to your load either powder, bullet or something else major as one component is not suited. If better, well try 25mm forwards and backwards and see if you can get the thing to a place where you are happy.
Thanks @grandpamac and @No.3 for more good thoughts.
I’d be surprised if the rings were over-lapped - as I recall, we barely had to remove any of the factory finish.
Crown damage - maybe? There’s a tiny ding in it, but it doesn’t appear to affect the bevel.
Re. the rebarrel - I believe this rifle had never been shot when I purchased it second-hand. As I understand it, an American client of a local guide brought it over but ended up using the guide’s rifle and leaving it here. I dunno if it was a custom or factory build, but it looks like they just a 7RM barrel.
A few pics of the items in question:
Attachment 250613
Attachment 250614
Attachment 250615
That be one of the worst looking crowns I've seen lately. Could be worth a go with a brass round head screw and some lapping compound. Jam an earplug into the muzzle level with the end and with a cordless drill on slow speed and a bit of fine lapping compound or even fine valve grinding paste give it a few revolutions and then check how it looks - just go until the crown is cleaned up evenly. I've had to do this once before, if it helps you might have found a glitch. Some pills are uber sensitive to uneven pressure and will not settle if they start out with a wobble...
I'd definitely send it off to smith to get the crown redone to eliminate that factor. It looks beat up to fuk.
As has been said the crown looks rough, it also appears that the rifling is damaged/not straight just inside the muzzle (about halfway down the visible part). Maybe the muzzle end of the barrel has opened up slightly when it was threaded.
I'd send it to a trusted gunsmith with instructions to cut an inch off the barrel and rethread, make sure you mention it's not shooting quite right and get them to check the barrel with a borescope first in case there's damage further up. I'd be sending the whole rifle to not just the barreled action, that way the smith will be putting it back together so no issues with mag binding etc.
Before you send it to the smith. alot of Remington rifles unbedded (is it bedded) shoot terribly without some form of barrel pressure point at the very foreend of the stock.. slip a business card up there and then group it.. some may notice some Remington factory stocks have small pressure points integrated into the fore end....
I've seen a .243 700 that shot 2-3" tighten up to 1/4 with that simple trick...
Secondly.. (ya can't fuck it more) you can do a simple recrown yourself before you send to smith with a drill and a case mouth camfer tool....
Delete the thread and put on TardMe... :thumbsup:
That crown yuck,chop chop.
the rechamber itself would raise suspicion with me. get a smith to have a look. had a 280 rem years ago and the chamber looked like it had been done with a cordless drill and a masonry bit...
So its been rechambered from 7mm Rem Mag to 7WSM ? That raises the needle on my weirdshitometer.
Greetings,
We have the winner, a badly damaged crown. I am amazed it shoots as well as it does. It looks like damage was done by rough handling. I have no doubt that the barrel is original to the rifle and originally chambered for the Remington short action ultra mag after comparing it with my own rifle. Who knows why. This may have been done some time back as the 7mm WSM has faded with the 7mm SAUM soldiering on in F - class. In any case the rifle is now a bitza but still worth cutting back the barrel enough to remove damage, if required, and re crowning to see if there are more demons from the rechambering. This would let you get some use from your components and dies. Not the answer you were hoping for but it is what it is.
Regards Grandpamac.
PS. The rifle would have originally had a 22 inch barrel. Handloads with projectiles of 150 grains and up would have seldom topped 3,000 fps.
GPM.
Thanks all! I'd assumed the crown would be fine as I've never carried it without the brake on, and I had that put on as soon as I got it... woulda thought the smith who did the threading for me might have looked at the crown, but there you go.
Yes @grandpamac - 22 inch barrel. Didn't want to shorten it further, but needs must.
Will take it down to Gunworks, but I'm also thinking of switching to a suppressor so I'll wait until a secondhand one comes up as I may have to get it re-threaded anyway.
gunworks will see you right..... probably looking at around the $400 mark for them to recrown,thread and fit brand new suppressor.
As fault finding and nothing to lose, try polishing the crown before you get it cut back. This is diagnostics time, as I said you are looking for improvements not a complete fix! Brass round head screw, grinding paste (it wont tear worse chunks) and polish until its even in the light. Try it again and see how it goes - push a patch through to clean everything out and also check for loose ares (bulges) in the barrel and at the muzzle.
Better?
Attachment 250665
MUCH better.....interesting to see what range result is.
Attachment 250670Quote:
Originally Posted by mopheadrob
Attachment 250671
Looks betterer to me, if grouping improves I'd still get the bore scoped before getting it professionally crowned.
Thought I'd post an update for the benefit of everyone who has offered advice & help.
Contrary to good scientific method, I changed everything at once :XD: Left the brake off and ran ladder tests on a number of different projectiles thanks to an awesome forum member. Tried 130 grain Hot-Cors, 162 and 180 grain ELD-Ms, 175 grain ELD-Xs and 180 grain Berger Hybrids. Accuracy was still shit, but I was only looking at velocity & elevation to get an idea of optimal charge. A couple of projectiles did show more promise than others though.
Then took off my Meopta scope and chucked on a Burris 3-9x40 and a Hardy Gen VI can. Back to the range to test 2 charge weights behind the Hot Cors (I'm loading these to SAAMI spec so they fit in my mag) and 3 x seating depths for each of the 162 ELD-M and 175 ELD-X.
The Hot-Cors shot one group of 3 rounds almost touching with a fourth about 0.75" to the right. The other group had about 1.25" of horizontal dispersion and 0.75" of vertical. I believe horizontal dispersion indicates poor seating depth, but as I don't want to seat them longer and it's only ever going to be a sub 200m load I'm happy with that.
All three x three-shot groups of the ELD-Ms were within 0.25" of the centreline. The group jumping 20 thou' had 2 in the same hole and a third 0.75" below them, but the 80 thou jump wasn't much worse. I'm happy with that too, but might try a touch more powder in case it tightens them up further.
What was most pleasing was the repeatability of the groups, with the two Hot-Cor groups having very little vertical dispersion and the three ELD-M groups almost no horizontal ruling out poor shooting technique, bedding issues etc. Hunting this weekend, then I'll swap the scopes back to see if it goes to shit again which will tell me if it was the scope or adding the can.
Thanks all for your input!
I'm stoked you have had such huge amount of progress. Your confidence will be good again yabbadabbadoo. Now go shoot something lol
Rechambered?
Rechambered??
I assume so - Model 7s would have come in 7SAUM and the barrel looks like it was a 7RMQuote:
Originally Posted by 6mm08
thats exact same speed as my 7wsm
