Belted casings questions

[mulerider]

First let me say I have searched the forum and still need opinons, I load for a coupled different belted magnums but experiencing problems with my 300 Win. Mag Sendero.

I have checked casing length 2.620 and have turned the necks, full length resizing, loading 208 Amax with 73.5 H1000 put still have a tight bolt when ejecting spent rounds.

The rounds chamber without any tightness or difficulty, just after firing bolt lift is easy just tight casing no shinny marks or other pressure signs on primer.

Holding about a inch at 200 yards and want to address the problem before I go any farther.

Suggestions???gun)

 

[gunpower]

First let me say I have searched the forum and still need opinons, I load for a coupled different belted magnums but experiencing problems with my 300 Win. Mag Sendero.

I have checked casing length 2.620 and have turned the necks, full length resizing, loading 208 Amax with 73.5 H1000 put still have a tight bolt when ejecting spent rounds.

The rounds chamber without any tightness or difficulty, just after firing bolt lift is easy just tight casing no shinny marks or other pressure signs on primer.

Holding about a inch at 200 yards and want to address the problem before I go any farther.

Suggestions???gun)

Have tried reducing your power back by a grain or two, to see if this still happens?
It sounds like the start of high pressure .

 

[Codyg510]

How long has it been since you cleaned the chamber? My rem 700 started doing the same thing a few weeks ago. The bolt would lift fine after firing, but the casing was stuck in the chamber. After the casing cooled i could eject it without problem.

It occurred to me that i had just cleaned the barrel, but not the chamber. Some cleaning agent combined with carbon buildup can make for a bad combo in the chamber. I went in and thoroughly cleaned the chamber (nasty, dang long-throated rems) and my next trip to the range went off without a hitch. No more stuck casings.

73.5 doesn't seem terribly hot for H1000 in a .300WM, but all rifles are different. Just doesn't seem like 73.5 would cause over pressuring.

 

[mulerider]

I will try cleaning the chamber and I agree that 73.5 grains don't seem like it should create the problem, several manuals list 75.5 as max for 220 grain pills
so I agree.

I will clean chamber and reload a few at lower charges and try again.

 

[Bart B]

I don't think the charge weight's too much; 77 grains of H1000 for that bullet's typically listed as maximum.

So, something else is causing the problem.

I'd take a loaded round then mark it all over its case with a black marker; use a lot then let it dry for 20 minutes to get it well dry. Then chamber and shoot it. Eject the case and see where the ink's rubbed off. That'll tell you what's happening.

 

[Grumulkin]

In a bolt action rifle, if the rounds chamber easily and the chamber is clean but bolt lift/ejection after firing is hard, the pressure is too high irrespective of what the load is or what the primers look like.

 

[backwoods83]

If bolt lift is easy or normal its NOT over pressure, bolt lift becomes stiff with an over pressure issue due to the case expanding a lot more than it should and pushing against the bolt. I did notice that the OP said he turned the necks, so how much did you turn them, if it was a good bit you have a lot of expansion in the neck and could cause issues. 73.5grns of H1000 is closer to a starting charge than a max for that bullet. I would brush and mop out the chamber though then do as Bart mentioned.

 

[Grumulkin]

Turning case necks will not cause excess pressure.

 

[backwoods83]

Really, I would have never figured that out, it cases excessive neck expansion and can make the cases hang or bind, even more so if they aren't evenly and smoothly turned, and if turned to much they will split and hang up. Btw I just started doing this yesterday!

 

[Bart B]

In a bolt action rifle, if the rounds chamber easily and the chamber is clean but bolt lift/ejection after firing is hard, the pressure is too high irrespective of what the load is or what the primers look like.

I've seen instances where a normal load in a round fired in a chamber where the bolt face is way out of square, the case head gets out of square and the bolt binds when it's opened. When the high point of the case head aligns with the high point of the bolt face (opposite from the low point at the fired case head's high point when fired), there's not enough clearance; the bolt binds. Especially if the case walls are uneven in thickness to cause more stretching on their thin side that just happens to be aligned with the bolt face's low point in its out of square condition.

 

[mulerider]

I had the sticky case before and after turning necks, I only took off the high spots, nothing severe.

I will clean chamber really well and reduce the charge and check, if that does not help then I will have gunsmith check for rough chamber or for something out of alignment.

Thanks for the replys, all good thoughts.

 

[silvertip44]

My 700 5R was having the same problem, stiff bolt lift and hard extraction. A thorough chamber cleaning and polishing eliminated the problem completely. Remington 40X bore cleaner on a cut down shotgun mop chucked in a drill and turned very slowly did the trick.

 

[Bart B]

Silvertip, now you know why the Garand service rifle has a bronze brush on this neat tool to keep their chamber's cleaned out of powder fouling so cases eject easliy:

Make your own with a large caliber or shotgun bronze bore brush in a short cleaning rod.

 

[silvertip44]

You are right about that Bart. I thought I was cleaning but it just wasn't good enough. I realized there was a small almost scratch like area just ahead of the belt on each case so that's why I polished it. If there was a burr in there the 40X got it out but I still clean the chamber thoroughly with a brush each time.