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tufrthnails
10-05-2016, 06:44 PM
So I loaded up a bunch of .270 with a known recipe that is my go to recipe. I checked to verify they cambered after a threw a couple together and finished loading the rest (200 rounds). First three I shot at range were pretty sticky I didn't have to beat the bolt back, but I did have to grab it and really yank it back. I looked at first sticky brass and the primer was ever so slightly cratered, but no other signs of pressure so I repeated that 2 more times. After the third one I put the rifle up and zeroed the AR and .243. I got back to the shop and pulled the bolt cleaned the hell out of the chamber. While I was doing that I seen something wierd in the corner of the chamber so i grabbed my bore scope and found a small piece of putty left over from the bedding job I did 2 years ago. I have put 100's of rounds through this thing since then. Countless chamber cleans. My question is could that have sealed something up causing the pressure spike? I havn't shot it since cleaning that out yet, but plan to tomorrow. I really really hope I don't have to pull 197 rounds.

JW
10-06-2016, 06:20 AM
Shoot some and see will be the only answer
Putty could have got picked up from the magwell on a shell
I have had putty show up later in the mag well from bedding

another thought is possible powder lot variations
I pulled 100 9mm one time with a kinetic puller- not a lot of fun
I hope you get it figured out
Jack

RC20
10-06-2016, 03:45 PM
I know there is a PE group that puts the whole issue onto lack of cam distance to extract.

I think FPE is far more accurate as it describe the situation but does not attribute a knee jerk cause.

My take is that its possible some are PE, but mine have been chamber issues that worked a lot better once I did a very good chamber clean (and long term will do a bit of polishing)

I am still looking for a low cost boroscope, but from what I can see in my OEM Savage chambers, the bluing rolls around the end and into the chamber where the base of the brass is and then is clean further in. I can see some odd color in the one chamber, not sure what it is. If not clean its causes varying degrees of shell stick.

the after market barrels have not done that, same bolts, no mods. .

Cleaning the chambers thoroughly stopped almost all of it in the Savage barrels.

So yes, clean, polish a bit maybe and see what happens. Report back please as this is important information.

Robinhood
10-06-2016, 04:22 PM
I'm one of those that believes that if a rifle has a feature designed to provide a mechanical advantage that aids in the extraction of a case It should be a priority to ensure that feature is operating as designed. If you are having problems extracting cases there is no other place to start than to ensure PE is taking place. If PE ramps are mating at the proper time and are providing enough leverage to remove the case, common sense tells you to then look to the brass, chamber or pressure.


If your car does not start it could be many things. If it does not turn over check the battery first, then the starter and or the ignition switch.

tufrthnails
10-06-2016, 06:44 PM
Thanks guys a little busy today with the whole hurricane thing, but I'll get out tomorrow and shoot a couple.

darkker
10-06-2016, 10:31 PM
So I loaded up a bunch of .270 with a known recipe that is my go to recipe.

If you are just loading the same grains of powder across any lot number, that well could be your problem. 10% variations across lots isn't unusual, and why it's warned about on the bottles.

Texas10
10-08-2016, 09:52 AM
I use this for inspecting the chamber, throat, muzzle. Works great. http://www.ebay.com/sch/i.html?_nkw=snap+on+bk5500

As for sticking bolt, what brass are you using? Could be soft brass is causing sticky bolt issues. Federal brass is reputed to be very soft and made to work ONCE as many here will attest to.

tufrthnails
10-08-2016, 06:24 PM
I use this for inspecting the chamber, throat, muzzle. Works great. http://www.ebay.com/sch/i.html?_nkw=snap+on+bk5500

As for sticking bolt, what brass are you using? Could be soft brass is causing sticky bolt issues. Federal brass is reputed to be very soft and made to work ONCE as many here will attest to.

I am using fed brass, but I have a batch with 6 loads on it and no issues I'm not loading screamers. This batch is split half has 2 loads half has 3 loads on it. I still have not got out to shoot with all the hurricane crap going on work has me tied up.

Scott Evans
10-10-2016, 07:25 PM
Don't get stuck in the 'Federal brass is always soft' mode, I picked up some 223 recently that is proving to be stronger than Lapua, and I had my initial doubts.

darkker
10-11-2016, 08:19 PM
Federal brass, in particular from their GMM ammo is VERY soft, for accuracy reasons. It is also not sold in the hopes that one day you will reload it for 20 years.
Always soft? Not likely. Can BE very soft, in particular in the head? Yes.

tufrthnails
10-11-2016, 09:04 PM
Well I kinda ended up with no specific answer. I finally got a chance to shoot some today. I don't know if it was clearing that piece of putty. Or scrubbing the chamber. Or I somehow loaded three hot rounds. I shot 22 round randomly drawn from to 4 boxes of 50ea and all of them shot and extracted flawlessly.

darkker
10-12-2016, 09:10 AM
Well I kinda ended up with no specific answer. .

I never saw that you answered my first reply.
Are you just loading "your recipe" by weight in grains?
If your go-to recipe gets followed, and powder lot variation gets ignored; you kinda have your specific answer.

yobuck
10-12-2016, 09:41 AM
So it ended up like the hurricane, not really a big deal. lol

tufrthnails
10-13-2016, 02:21 AM
Sorry I didn't see the question. Yes I do load by weight in grains. And yes I have been following the weight vs volumn debate. But it doesn't apply here because somewhere there was an issue with the rifle I just don't know what exactly fixed the problem.

darkker
10-13-2016, 04:01 PM
1) Yes I do load by weight in grains. And yes I have been following the weight vs volumn debate.
2) But it doesn't apply here because somewhere there was an issue with the rifle I just don't know what exactly fixed the problem.

2) I'm glad you got the problem sorted out, but back to #1 for sake of knowledge.
1) Volume Vs. Weight methods aside, you should understand burning rates.

If you are simply using brass "signs" or sticky extraction as your judge of pressure, you are missing important info.
Most US brass producers test brass for roughly 125% of case operating pressures(SAAMI MAP). So when you notice something wrong, you are well over pressure. Follow your Chrony readings to know whether or not you are over-pressure. The method you use to load aside, ignoring the "Drop 10% when switching lots" warning, and simply assuming that all powders will have the same burning rate can be dangerous. Our Pressure Trace work is by no means all encompasing, but have found several lots of powder that are different from the last by 8 - 12%; and to be fair some are essentially indistinguishable, even when testing the same "name" on the bottle.
In the newest Norma manual there is a very good article on how much moisture can change even from "sealed" containers, leading to large shifts in burning rates.

tufrthnails
10-14-2016, 02:38 AM
Cool I see what your getting at. Your right I should have sent them across the chrony when I switched bottles. That will definitely be at the front of my thought process.

tufrthnails
10-15-2016, 10:08 AM
Took the .270 along with the 6.5 back to the range yesterday. Problem is definitely cleared up. Shot 9 rounds from each of the 4 boxes of 50 I got loaded. I shot and extracted beautifully. So happy I got to learn a good lesson without having to pull 100ish bullets! No POI change across the boxes. At 100yards. I'm taking it when I go stretch the 6.5 out to 400 in a couple weeks and that should truly tell me if there is any POI change. Wish I had a longer range less then an hour and a half away.