What was that?!?

[mis-guided child2]

Heres the situation. Rem Sendero II. 300 RUM.All Big green.

Sexy aint she?!?
New rifle, less than 120 down the tube. All of which have been factory fodder.
I did quite a bit of reading on the subject and had on hand some 190 SMK's and H1000.

So i rolled up some proof rounds just to check pressures. All brass was F/L sized with RCBS dies, second fire RP's. Basic prep work. CCI 250 primers. H1000 and 190 gr SMK's.
I started at 85.0gr with a 3.675 seating depth which gave me right at .100 jump.

I loaded in 1/2 grain increments( just 1 each per load) up to 92gr. Again, I was just looking for pressure.

ALL of the factory rounds show signs of primer flow around the firing pin indention.

Sooooo.... 85gr had no primer flow, mild recoil, no issues with bolt lift etc, I progressed forward.
Everything progressed normally through 88.grains. Primer flow, recoil, everything went up accordingly. At 88.0 gr my primer was somewhat flattened, but edges were still nice and round, flow was pushed back in respectively, no issues with bolt lift.
88.5 gave me a flat primer, the entire dimple was evident but flattened, bolt lift was normal.
I contemplated calling it good, but i wasnt close to book max.
which I believe was 92.3( but dont quote me on that!)
After some careful consideration, I touched off 89.0.
I had moderate primer flow, no flattening at all of primer, and normal bolt lift. Everything increased again with each shot
until 91.5 at which point I had heavy primer flow and a semi flattened primer at which point I quit.

Ive never experienced a pressure "node" before. Have you? Insight from the masters please.

 

[desertHK]

Re: What was that?!?

I would consider trying the 208 AMAX or the 210 VLD. My friend has one and he shoots the 210 VLD. the result is very impressive. The 190 grains projo is good but begins to loose its effect when you are stretching it to the range that the RUM can perform. Just a thought.

 

[mis-guided child2]

Re: What was that?!?

Im with ya on that line of thought. And everything I have read points in the same direction. And I will go there.

My concern is with the possible midrange pressure spike though. Not necassarily the best load.

Maybe I simply had two "Looser" primer pockets in succession. Who knows.

 

[mis-guided child2]

Re: What was that?!?

Anyone?

 

[desertHK]

Re: What was that?!?

First off, do you have a chamber length for your stick? 3.675" is not that much longer than the cook book calls for which is 3.600". However, if you are ramming it into the lands then it may create some pressure issues.

Second what kind of velocity are you getting with the various charges you are working on. A poor man's gauge for the max for your stick is a plateau of the velocity with increasing powder charges.

Thirdly, what kind of groupings are you getting? IMHO, you just need certain speed to optimize the performance of your projos. Beyond which, you are just chasing the speed demon at the expense of accuracy.

 

[mis-guided child2]

Re: What was that?!?

My bolt closed at approximately 3.750.(i do not have my notes with me, but can get them if needed) Which is why I stated giving me almost a one hundred thousanths jump.I meant jump to the lands. I should have been more specicfic. I worked down from there until the round would fit and feed from the factory magazine well. I am confident I was not near the lands.

Again. I was only looking for indications of maximum pressure, in my gun, with the stated loads. I did not carry my chrono with me. I simply was after pressure signs, if any. It was not my intent to find the most accurate load, nor the fastest load. I was only after pressure signs. Pressures indicators give me a good idea of what not to do/ exceed for a specific load/rifle.
I use it as a starting/ending block, so to speak. After, and only after I determine my safe operating envelope for a specific powder/ bullet combo in a specific firearm will I go back and attempt to develop the most accurate load.

Again sir. as earlier stated, I loaded one each in half grain increments. I did not shoot for groups. Groups will come later.
My sole purpose was to find this particular rifles safe envelpoe for the specified powder/ bullet combo.

I can type slower if needed for comprehension skills.

 

[desertHK]

Re: What was that?!?

No problem with comprehension on that. LOL. It's a good way to see what your powder range is before loading for groups. Should have read your OP a bit more carefully before posting. I use that method for my 50 BMG.

IMHO, stiff bolt can sometimes be difficult to "perceive", unless you need a sledge hammer to open the bolt. You bolt closes at 3.750" so you still have room to go. As I mentioned before, when in doubt, I chrono my rounds with various powder charges to see if the velocity changes with increasing powder.

If velocity remains the same and signs of primer flattening, and stiff bolt then I would say you are at the ceiling. For me just lifting the bolt can be difficult to perceive if it is "sticky" or not.

 

[Win70chris]

Re: What was that?!?

I have the same thing happening with my PSS in 300 RUM. I am using 190smk's with 91gr Retumbo. Mine are showing primer flow with round edges but no other signs. This is what I was told

--------------------------------------------------------------------------------

Nope you are probably fine. Some rifles make the little crater in the primer some don't. Just note the shape and size of your crater and if it starts to change that may be a sign of pressure. The things I watch for over pressure are
1 Sticky bolt
2 Shiny spots on head stamp if they start appearing or get worse or smear
3 Case head expansion they say about .001 is all you want to experience
4 Primer pocket expansion. once you hit .2085 they will start being quite loose
5 Velocity
Keep going with what you are doing.

 

[mis-guided child2]

Re: What was that?!?

I'm comfortble with the primer flow.

My question is concerning the the flattening of the primer
in a mid range load. And not being there at higher charges.

 

[Victor N TN]

Re: What was that?!?

Have you noticed that the MINIMUM CHARGE for that powder and chamber combination is at 92.0 and the max is at 97.0 ?

The cause of the pressure spike is the bullet is still in the barrel long after it should be. In the realm of "nano seconds" there was a lag (be it ever so slight) in the bullet getting out of the barrel. These loads are meant to be used between the minimum and maximum loads only. That's one reason people blow up perfectly good rifles. You can blow up a rifle using below minimum powder charges as quick as over charging them.

I suggest you buy a copy of Lyman's Centerfire Handloading manual and read it. If you already have a copy of it, read it again. You missed something the first time. Or you have forgotten it.

 

[ChadTRG42]

Re: What was that?!?

I'm showing a minimum of 88 grains and a max of 93 grains on Hodgdon's website for a 190 grain bullet and H1000. If you seat the bullet out further, your max can decrease from this slightly. I don't have my other manuals to view other data with me.

On your primer flow, it is not uncommon to have primer flow around the firing pin hole from the hole in the bolt. So, I do not use this as a pressure indicator for loads. Each rifle shows different amounts of primer flow, so it's difficult to relate it to pressure. The main two things I use are ejector marks on the case head and sticky bolt lift (in that order). You will see shiny, flattened marks and/or round ejector marks on the case head when you reach pressure. You may or may not get sticky bolt lift with these signs. But you will get sticky bolt lift if you go above the shiney spots indicators.

I would progress up to the 93 and even slightly beyond it to see what you get. If you have a chrono, it will help to know where you are.

 

[Shady_Jay]

Re: What was that?!?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: misguided child2</div><div class="ubbcode-body">I'm comfortble with the primer flow.

My question is concerning the the flattening of the primer
in a mid range load. And not being there at higher charges. </div></div>

I thought you were going to make the trip out here to avoid all of this? lol

 

[mis-guided child2]

Re: What was that?!?

Chad-Hodgdon web shows starting loads 88.0
but didn't list minimum. Maybe that's reading into it too much on my part.
I also referenced reloaders nest and long range hunting websites, as well as the my newest hornady manual which is where I got my minimum and minimum loads.

Victor- my Lyman manuals are old enough not to cover the 300 RUM.
But unless all my sources are incorrect your Lyman manual has some bum scoop on that particular load. I wouldn't be passing out those powder charges to my friends if I were you. Dude, are ya trying to kill me? Lol. I don't remember pissing ya off!

 

[mis-guided child2]

Re: What was that?!?

CKA. I'm gonna make the trip so we can have some quality 1 on 1 time!
Not for your reloading info. Just saying!

 

[ChadTRG42]

Re: What was that?!?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: misguided child2</div><div class="ubbcode-body">CKA. I'm gonna make the trip so we can have some quality 1 on 1 time!
Not for your reloading info. Just saying! </div></div>
That would be a great idea!!! and for reloading!

 

[mis-guided child2]

Re: What was that?!?

I asked if anyone else has ever experienced flattened primers in a mild load, when the primers looked fine at lower charges and looked fine at higher charges.

So far the replies have been:

1-Change bullets
2-Read a reloading manual(which by the way was the only response remotely about the question)
3-Dont worry about primer flow
4-Have Captain Kick Ass sprinkle his magic reloading dust on it.

Lemme try to reword it!

Look here. I made me some boolits. Some had a little powder in em, some had more than a little powder in em, some had alot of powder in em.
them there boolits in the middle, with more than a little powder but not alot of powder was flat on that little shiny thing I put in the end. Them other boolits i shot, them little shiny things looked A-ok.
Reckon what that was?

 

[Shady_Jay]

Re: What was that?!?

lol or pay Chad to make them for you

 

[Grump]

Re: What was that?!?

Single-sample size is too small to reliably tell anything.

Repeat with 3 apiece, AND gather the additional data available from the chronograph. If two steps in a row show a lot less speed gain per step compared to the others, I'd stop regardless of pressure signs. "Signs" appear AFTER you're over-pressure.

Don't worry too much about whether your speeds match the book loads. Even if you duplicate every component and barrel, some rifles will shoot up to 200 fps different from others. My 22-inch in .308 shoots almost the same speeds as the 26-inch Savage in the Sierra book. One of Sierra's reputably "conservative" loads is WAY higher than I can safely use in my rifle.

More data = good = might be able to draw an intelligent conclusion.

In general, one single "pressure sign" without any others is usually not a problem. Can't make a guess, though, based on a single event. The blind pig and the acorn, you know. Good pig for acorns??? Worked once!!!

 

[mis-guided child2]

Re: What was that?!?

Good point Grump. Thank ya.

 

[Victor N TN]

Re: What was that?!?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: misguided child2</div><div class="ubbcode-body">Victor- my Lyman manuals are old enough not to cover the 300 RUM.
But unless all my sources are incorrect your Lyman manual has some bum scoop on that particular load. I wouldn't be passing out those powder charges to my friends if I were you. Dude, are ya trying to kill me? Lol. I don't remember pissing ya off!
</div></div>

I just read them out of the book. While Lyman's in my favorite. I have manuals from every major maker. ALL will differ on a lower and upper limit. I promise I wasn't trying to kill you.