Pressure signs in a Rem 5R

TFin04

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Minuteman
Dec 13, 2009
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Livingston County, MI
I'm working up a load in my 308 5R factory rifle. Using 4064 powder. Max load is 45.5 grains which is slightly compressed in Win brass.

I've gone up from 90% to max load. I don't have any ejector flow or head stamp deformities. I DO get primer flattening and slight primer flow even on minimum loads and on cheap factory 147gr blasting ammo. On my hotter hand loads I notice a very slight case bulge (I hesitate to even call it a bulge but you can see a difference in the case). It's about 1cm from the back of the case.

I've seen some say to load until you see ejector flow and some say no primer flattening at all. Minimum loads are flattening primers so I am confused.

Given the info above, what would you guys use to keep an eye on pressure?
 
The charge isn't the only thing that plays into pressure. Check your head-space and seating depth. Too much head-space can cause the problems you mentioned as well as seating the bullets into the lands. Of course you could be overloading them too... The take away point here is that you need to look at many more factors than simply assuming it's a charge issue.
 
Does that info help with diagnosis at all?

Not really. Every rifle is different so you can't base what's happening in yours to others even of the same type/brand. You simply have to buy the tools and do the measurements yourself. Get a head-space gauge and OAL gauge, these will show you exactly what your chamber is like and how far out you can seat your bullets. 45.5gr of 4064 is s pretty reasonable load for a 308 with Win brass so the fact that you're seeing these pressure signs means you probably have something else askew it could be any number of things such as a head-space issue, seating depth, shitty brass, etc. so you have to start with the easy things such as head-space and OAL.
 
I had flattened primers from 40gr up (my starting load). I hit a node around 42 and another around 44.5.

This rifle is flattening primers on every load I've shot through it, so I'm thinking it may be a headspace issue. I'll get that checked out and probably explore the node at 42.

I'm using IMR data which has maxes of 45.6 for 175gr, and 45.2 for 180gr. I do have some 178 AMAX's I'd like to play with, but I was trying to nail down an SMK load since this rifle loves FGMM.

Thanks for your help guys.
 
Do not ignore the pressure signs. All the signs are there, you are just choosing to ignore them. There is likely nothing wrong with your rifle. The load is just too hot and you don't want to admit it.

45.5 grains 4064 in any case with 175 SMKs is a hot load. I don't care what anyone says.
 
I went back to inspect my cases. They have been tumbled so I don't know exactly which load these are, but I loaded a total of 4 cases at 45.5 and these four are the worst, so I have to assume these are them.

I am posting them for an opinion. To make it perfectly clear to guys like TacticalBoltKnob...I understand these are pressure signs.

Do you guys use ANY primer flow as an unacceptable pressure sign or do you grade them on sevarity? I do have a handful without any primer flow but those were in the 39-40 grain range and my goal is a load I can take to 1000, so I was hoping for a bit more ass than a minimum load.

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The point is that you already have pressure signs and you have identified them. Whether you heed those signs is up to you. You can beat the hell out of your gun and suffer short brass life, but the pressure isn't going to go away.

Have your chrono'd your loads to see where your velocities are?
 
The point is that you already have pressure signs and you have identified them. Whether you heed those signs is up to you. You can beat the hell out of your gun and suffer short brass life, but the pressure isn't going to go away.

Have your chrono'd your loads to see where your velocities are?

If you read my original post, you'd see that your assumption is off the mark. My question was in regard to the varying opinions on which signs are important and which ones are not.

I have not had the opportunity to chrono these loads.
 
primer flow even on minimum loads and on cheap factory 147gr blasting ammo.

I had flattened primers from 40gr up (my starting load).


Do not ignore the pressure signs. All the signs are there, you are just choosing to ignore them. There is likely nothing wrong with your rifle. The load is just too hot and you don't want to admit it.
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I think he's clearly having an issue that is not related to an over charged load and he said as much several times in this thread including his very first post. OP, like I said before you really need to get the tools I mentioned above and check out what's going on in your gun before you keep shooting it.
 
I can live with flat primers, and I don't think yours look all that flat. The primer flow or "pooch" is a characteristic of a 700 bolt. To me, you need to pressure it up till you get an honest ejector hole, and back off from there.

Running the load through a chrono can help explain a lot.
 
I think he's clearly having an issue that is not related to an over charged load and he said as much several times in this thread including his very first post. OP, like I said before you really need to get the tools I mentioned above and check out what's going on in your gun before you keep shooting it.

I agree it's safe to make sure the rifle doesn't have an issue. But I stand by my statement. Some loads manifest certain pressure signs and some don't. Sometimes the pressure signs are different. But I don't think you can cherry pick which are important and which aren't, especially when you are running at max loads per published load data or at the bottom end of the load data. That is where you start to get into trouble, in my opinion.
 
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Thanks for the input guys, it is appreciated.

I got some input from a well respected individual in the precision world and he thinks they are normal 700 primers. His opinion was that sticky bolt lifts and ejector swipe were the most important criteria.

I am going to confirm any headspace issues and explore the node around 42gr and go from there. I don't think the situation is as bad as I originally thought. My interpretation on "flat" primers seems like it was too strict according to a few other sources.
 
When you check your headspace, don’t freak out when the bolt closes on a nogo gauge... I have yet to come across a 308 parent case chamber in a factory Remington that wouldn’t. FWIW, all have passed (will not close) on a field gauge.

As others have said, depending on the brand of brass used, you should find a node +/- .2 of a grain around both 42 and 43 grains with 175’s. While I don’t see ejector swipes on your headstamps I would say you most definitely are over pressured at 45.5 or you have a very slow lot of powder. This assumes we are talking about IMR4064

I am curious if you know what your velocity is though...
 
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I'd agree that those don't really look flat, but the flow around the firing pin looks like typical 700 issues. I have two of them here that do that with factory ammo.