Out of Ideas!!!! High Pressure in Everything

[Fisky]

Factory Rem 700 SA, 308 Win, 800 or so rounds through it
155 Scenars, Lapua Brass, Varget


Long story short, I started getting high pressure in a new load I had worked up recently, which during load workup I wasn't getting much for pressure signs except an occasional ejector mark here or there. It has progressed. I now get high pressure in everything I put through my rifle (even my old load that I've shot approx 700 times with no pressure). I've read, researched, and talked to a gunsmith. I've eliminated most all variables. After this mornings session I am now 99% confident it's my barrel.

This morning was a test to rule out one sizing die or the other, and do a quick ladder test at the same time. I loaded up some LOW charges of 45.4-46.2 Varget in .2 increments. I loaded up 1 rd of each in brass sized with a RCBS FL and FOrster FL. I cleaned the hell out of my barrel and chamber few days ago so I decided to shoot a couple of my higher charges of 47.4 to foul the barrel, and see if my cleaning had improved anything. I put 3 of them through it with no signs of high pressure. So I proceeded with the ladder test.

Once I got to the first 45.8 charge I started getting ejector marks. Sticky bolt and ejector marks grew from there, with everything.

My barrel is fouling after 5 rounds to the point it is causing high pressure in loads that aren't even close to max. What is going on here, and what are my options? Try hand lapping or fire lapping?? Will it do any good at this point? It's a good shooting rifle, and I have a lot of 308 components on hand. If I rebarrel it, it probably won't be to a 308, so I'd like to get this problem solved for now so I can shoot up my 308 stuff and go from there.

Thanks

 

[MEDICGORDO]

Re: Out of Ideas!!!! High Pressure in Everything

How fast are they running?

 

[wnroscoe]

Re: Out of Ideas!!!! High Pressure in Everything

First, clean and inspect for a carbon ring.

Then try H4895, CCIBR2's, Lapua Brass, 155 Scenars or 175 SMK's. Start at 41 grains and work up to pressure or bugholes. If it doesnt shoot this combo your rifle is broken.

 

[blackblue]

Re: Out of Ideas!!!! High Pressure in Everything

Accurate charge weights?

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

Here are the velocites from this morning...I got many pages of data like this, as I've been troubleshooting this for awhile. If you need more, let me know.

47.4
2879
2879
2898
2898

45.4(RCBS/Forster)
2807/2754

45.6
2830/2818

45.8
2849/2830

46
2795/2842

46.2
2867.2861

COAL is 2.800", not even close to the lands in that factory chamber...

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: blackblue</div><div class="ubbcode-body">Accurate charge weights? </div></div>

Confirmed by two scales...

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wnroscoe</div><div class="ubbcode-body">First, clean and inspect for a carbon ring.

Then try H4895, CCIBR2's, Lapua Brass, 155 Scenars or 175 SMK's. Start at 41 grains and work up to pressure or bugholes. If it doesnt shoot this combo your rifle is broken. </div></div>

I cleaned for a carbon ring just a couple days ago. I don't have a borescope. But with the amount I've cleaned this thing the last week, I'd think a carbon ring would be removed. I haven't used any abrasive cleaner yet, however. May try some JB borepaste next, I don't know.

 

[wnroscoe]

Re: Out of Ideas!!!! High Pressure in Everything

Try the load I suggested, you might be surprised. It's been money in every Remington 308 I've shot.

 

[Boltfluter]

Re: Out of Ideas!!!! High Pressure in Everything

Is this a new lot of Varget?

Regards, Paul

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bolt fluter</div><div class="ubbcode-body">Is this a new lot of Varget?

Regards, Paul
</div></div>

No.

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: wnroscoe</div><div class="ubbcode-body">Try the load I suggested, you might be surprised. It's been money in every Remington 308 I've shot. </div></div>

Where do you usually end up around for charges with the 155's, and ballpark velocity?? Thanks

 

[Kells81]

Re: Out of Ideas!!!! High Pressure in Everything

Did you just start using Lapua Brass?

Between Rem Brass and Nosler brass I have a full grain difference in where I can load them without getting signs. Nosler shows signs where Rem won't in my rifle.

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Poke</div><div class="ubbcode-body">Did you just start using Lapua Brass?

Between Rem Brass and Nosler brass I have a full grain difference in where I can load them without getting signs. Nosler shows signs where Rem won't in my rifle. </div></div>

Yes, for the most part all this pressure crap started when I went to working up a new load with Lapua brass. I also cut 4" off my barrel and had it threaded. My old load at 26" was Rem brass and 46gr varget, at 2850fps. Thing is, I've put what I had left of this old Rem load through the rifle since this pressure started, and I was even getting sticky bolt and ejector marks with that load now. Shot it approx 700 times prior to this with no pressure issues.

I'm going to try some factor Federal ammo next time out too. And maybe tap into a new keg of Varget as well.

 

[Conrad]

Re: Out of Ideas!!!! High Pressure in Everything

So when you say you put your old Rem load through the rifle, I'm assuming that included the rem brass and you got pressure signs? Or did you load the "rem load" into your lapua brass? If the latter could be dealing with differences in case capacity between the two. Also you said you're comparing different sizing dies; I'm assuming you're bumping shoulders .002-.003" on fired brass? Simply trying to rule stuff out, but you didn't size your new Lapua brass before shooting it did you? That'd result in less capacity and possible headspace problem that could show pressure signs. Do you have any of your old fired brass before the problem started that you can measure and compare to brass that is showing problems. Your idea on trying some factory ammo is good, could give you some insight. After that try the H4895 load.

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Conrad</div><div class="ubbcode-body">So when you say you put your old Rem load through the rifle, I'm assuming that included the rem brass and you got pressure signs?

<span style="color: #FF0000">Correct, "old load" = Rem brass load with the 26" barrel...</span>


Also you said you're comparing different sizing dies; I'm assuming you're bumping shoulders .002-.003" on fired brass? Simply trying to rule stuff out, but you didn't size your new Lapua brass before shooting it did you? That'd result in less capacity and possible headspace problem that could show pressure signs.

<span style="color: #FF0000">It's all been new Lapua brass, ran through the FL sizer die, and loaded up for load testing. Both dies have been set up per the instructions. I haven't set them up to bump the shoulders yet. Maybe I should do that on some once fired stuff and see what happens??</span>

Do you have any of your old fired brass before the problem started that you can measure and compare to brass that is showing problems. Your idea on trying some factory ammo is good, could give you some insight. After that try the H4895 load. </div></div>

I do have some old Rem brass I can compare with some recently fired stuff. What specifically would you measure?

Thanks

 

[Beepy]

Re: Out of Ideas!!!! High Pressure in Everything

Possible brass not trimmed enough, too much stretch?

 

[SPAK]

Re: Out of Ideas!!!! High Pressure in Everything

Have you had the headspace checked?? Although I don't know why your headspace would be off unless you've had some barrel work done at all.

But excessive headspace can produce signs of excessive pressure, so can left over lube on the cases that hasn't been wiped off completely.

the condition would be more pronounced with new brass since new brass is usually on the small side to begin with.

I'd have someone with some headspace gauges just run them in there and see if it all checks out. Just to be sure.

Excessive throat erosion might cause pressure problems as well. I've had a rifle with proven mild load that shot great start showing pressure signs. Had the bore scoped and it was cooked...

Just some thoughts.

 

[Conrad]

Re: Out of Ideas!!!! High Pressure in Everything

[/quote]
I do have some old Rem brass I can compare with some recently fired stuff. What specifically would you measure?
[/quote]

Get a comparator like what Hornady sells and compare the length from the base of the case to the shoulder.

A 9mm case might work in a pinch but contacts slightly above the midline/datum line of the shoulder.

I didn't do a good job of describing what to compare. Compare this measurement from new lapua to fired lapua. Then also compare sized rem brass to fired rem brass.

However, the fact that you said your old rem brass load showed pressure also could indicate the issues described by Frogman and Beepy. Hard to believe your .308 barrel is toast though. Check your trim length.

See what your measurements show you on the headspace. Curious if the smith didn't get the barrel fully tightened? Would be strange, but I guess possible. Or your new brass is just small which is not uncommon. Bump shoulders on fired brass and see if it cures your problem. If you aren't setting your sizing die up with some kind of comparator off of fired brass you need to be.

I simply run a sinclair expander mandrel into the necks of my new brass, no sizing die, when loading new brass.

Hope you get it figured out.

 

[wnroscoe]

Re: Out of Ideas!!!! High Pressure in Everything

175's will be around 41.5 to 42.0, 155's maybe around 43-43.5

 

[Who Dat]

Re: Out of Ideas!!!! High Pressure in Everything

Two things are very possible the first would be case wall thickness. The Lapua brass may be thicker then what you have been shooting and it will show excessive pressure signs with the same powder charge that you normally use in your other brass. The other would be failing to trim back your cases which will also give you pressure signs. A lot of reloading data states you need to reduce your load if you use Winchester brass because of wall thickness. Cutting your barrel down would have nothing to do with pressure signs, you would just loose velocity because not all of the powder will burn before the bullet leaves the barrel. Purchase a box of match ammo and take it out and shoot it. I am pushing a 168gr Hornady AMAX at max charge weight using Varget and I am having zero pressure signs out of my Remington with a factory barrel. Good Luck

 

[shoot4fun]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Fisky</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Poke</div><div class="ubbcode-body">Did you just start using Lapua Brass?

Between Rem Brass and Nosler brass I have a full grain difference in where I can load them without getting signs. Nosler shows signs where Rem won't in my rifle. </div></div>

Yes, for the most part all this pressure crap started when I went to working up a new load with Lapua brass. I also cut 4" off my barrel and had it threaded. My old load at 26" was Rem brass and 46gr varget, at 2850fps. Thing is, I've put what I had left of this old Rem load through the rifle since this pressure started, and I was even getting sticky bolt and ejector marks with that load now. Shot it approx 700 times prior to this with no pressure issues.

I'm going to try some factor Federal ammo next time out too. And maybe tap into a new keg of Varget as well. </div></div>

Quite possible that the key to your problem is in this post. You had 4" cut off the barrel and threaded. If the barrel was not properly reinstalled then you have a head space problem. If you have a barrel vise, put the BA in the vise and make sure it is tight on the action.
If not, and the gunsmith who did the work is nearby, take it to him and get that checked out.

 

[SPAK]

Re: Out of Ideas!!!! High Pressure in Everything

I missed the part about the barrel being cut and threaded..... I would definitely have your headspace checked... It doesn't take much to run some gates through it.

In the meantime, take some if the fired brass and measure the difference between them and new brass to the shoulder and see what you come up with..

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

Here are some numbers for you guys....I'll let you decipher it for me.

Used my Sinclair Bump Guage for the first time tonight...

New Rem
1.554-1.555

FL Sized 2x fired Rem
1.553

Fired Rem with high pressure signs
1.560-1.561


New Lapua
1.550

FL Sized New Lapua
1.550

Fired Lapua
1.559-1.600


A little more testing tonight too, factory ammo...

165 SGK Federal Stuff (4 shots, 2712fps)
-sticky bolt and ejector marks

150 Winchester Soft Points (I believe) 8 shots, 2802fps
-NO pressure signs


You guys tell me what to make of this. Thanks

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

Also, case length is not the issue here. All brass seems to come out of the die 5-7 thou below max case length....

 

[xdeano]

Re: Out of Ideas!!!! High Pressure in Everything

That's your issue. The case has to grow a lot to fill that chamber and in doing so it'll slam against the bolt face giving you extra pressure and brass flow and give you ejector marks. Giving you the impression that you're over pressure.

Take it back to the smith.

xdeano

 

[xdeano]

Re: Out of Ideas!!!! High Pressure in Everything

Take a look at the specs. they should be close.

http://www.6mmbr.com/308Win.html

xdeano

 

[shoot4fun]

Re: Out of Ideas!!!! High Pressure in Everything

<span style="color: #990000">You guys tell me what to make of this. Thanks</span>

We have.

CHECK THE HEADSPACE!!!!!!

I think your smith left the barrel loose.
Tighten it down RFT.

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

Yeah, it appears the problem has been found. Appreciate the troubleshooting help....

Fisky

 

[shoot4fun]

Re: Out of Ideas!!!! High Pressure in Everything

Sorry to be rude but some folks just go on and on when we can't give a hands on evaluation. It had to be something that took place during the time the rifle was being worked on.
Good luck with the fix.
S4F

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: shoot4fun</div><div class="ubbcode-body">Sorry to be rude but some folks just go on and on when we can't give a hands on evaluation. It had to be something that took place during the time the rifle was being worked on.
Good luck with the fix.
S4F
</div></div>

No worries. I should have known better (well I do now), that the timing was more than a coincidence. Had I actually thought it through, it could have saved me a lot of time and BS, as well as a couple others...Lesson learned.

Thanks

 

[Conrad]

Re: Out of Ideas!!!! High Pressure in Everything

Good learning experience, and good job on the measurements and learning what is going on. What Xdeano described is right on the money. Should have it back in working order shortly.

 

[xdeano]

Re: Out of Ideas!!!! High Pressure in Everything

You may want to separate those brass that you fired from the group and check for incipient head separation before they return to the herd. Or you may have some issues with separation later on.

Use a dental pic or a paper clip bent straight with a hook on the end sharpened down. Reach down the case and scratch back up the inside of the case to see if it catches anywhere. If it does, it goes into the garbage. Go around the entire inside of the case.

xdeano

 

[300sniper]

Re: Out of Ideas!!!! High Pressure in Everything

i personally doubt headspace is the issue. the difference between hand tight and fully torqued is going to be minimal enough that it's not going to cause a huge pressure increase.

for shits n grins, were there any manufacture/caliber markings on the barrel? are they in the same spot now as they were before?

 

[waste_knot]

Re: Out of Ideas!!!! High Pressure in Everything

Did you change the barrel lug? Did the smith give youa headspace dimension?

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: waste_knot</div><div class="ubbcode-body">Did you change the barrel lug? Did the smith give youa headspace dimension? </div></div>

No, and no..

 

[XTR]

Re: Out of Ideas!!!! High Pressure in Everything

Is this a custom chamber or a stock chamber.

What is the neck size?

If it was cut with a tight neck reamer switching from RP to Lapua may be too tight to release the bullet.

Measure the neck on some fired cases. If it is less than .340 that may be your problem.

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 300sniper</div><div class="ubbcode-body">i personally doubt headspace is the issue. the difference between hand tight and fully torqued is going to be minimal enough that it's not going to cause a huge pressure increase.

for shits n grins, were there any manufacture/caliber markings on the barrel? are they in the same spot now as they were before? </div></div>

The rifle isn't with me right now, but I'll take a glance at that when I get a chance..

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: XTR</div><div class="ubbcode-body">Is this a custom chamber or a stock chamber.

What is the neck size?

If it was cut with a tight neck reamer switching from RP to Lapua may be too tight to release the bullet.

Measure the neck on some fired cases. If it is less than .340 that may be your problem. </div></div>

Stock chamber

 

[Chiller]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 300sniper</div><div class="ubbcode-body">i personally doubt headspace is the issue. the difference between hand tight and fully torqued is going to be minimal enough that it's not going to cause a huge pressure increase.

for shits n grins, were there any manufacture/caliber markings on the barrel? are they in the same spot now as they were before? </div></div>

would love to hear your logic on the why?

5-7 below case would seem HUGE and would seem to allow for MUCH more flow than normal?

 

[300sniper]

Re: Out of Ideas!!!! High Pressure in Everything

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Chiller</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 300sniper</div><div class="ubbcode-body">i personally doubt headspace is the issue. the difference between hand tight and fully torqued is going to be minimal enough that it's not going to cause a huge pressure increase.

for shits n grins, were there any manufacture/caliber markings on the barrel? are they in the same spot now as they were before? </div></div>

would love to hear your logic on the why?

5-7 below case would seem HUGE and would seem to allow for MUCH more flow than normal? </div></div>

You are not going to gain or lose 5-7 thousandths by removing/reinstalling a barrel. You may have a 2 thou difference between hand tight and fully torqued. If a wrench was put on it, I'd bet there's less than a thou didderence between the before removed hs and reinstalled hs.

I assumed the 5-7 thou refrence was trim length, not headspace.

 

[sako.308]

Re: Out of Ideas!!!! High Pressure in Everything

i shoot almost same exact loading you have

R700
.308
lapua 155 scenars
varget- 44 grains


only veriable i could see would be the seating deapth or maybe lack there of. and according to my book using 155 and varget 45.6 is a MAX load

 

[Who Dat]

Re: Out of Ideas!!!! High Pressure in Everything

Sako.308,

I have to agree with you on depth for bullet seating which could also have an impact on pressure signs whether that be in or out for OAL.

 

[xdeano]

Re: Out of Ideas!!!! High Pressure in Everything

You guys, he's shot factory rounds too, and found that they were over pressure. It all points back to the barrel not being on correctly, right? It could be a revolution off. The seating dept thing will change your pressure sure, but it goes right along with your chamber being longer than it should be. So you have to jump that much more.

The reason I told him to cull those cases until he has no head separation is because I'd rather him be safe then sorry. For no other reason than that. And just brass does allow quite a bit of flow but once that head sapartation starts it's easy for it to continue.

Get the barrel checked and get back to us. I'm curious.
xdeano

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

Deano, I'll be contacting somebody tomorrow to take a look at it. I'll let you know what I find out when I learn something.

I'll be sure to check them cases over before I throw them back in the pile too.

Thanks

 

[Who Dat]

Re: Out of Ideas!!!! High Pressure in Everything

Xdeano,

I will have to agree with you if there is no room for brass growth upon firing that will cause serious issues depending on powder load. The bolt could lock up and that is a pain with a Remington because we all know the handles are soldered on and could detach when forcing it open.

 

[300sniper]

Re: Out of Ideas!!!! High Pressure in Everything

So, are the factory markings in the same position as before the barrel work? Unless machine work was done at the chamber end, I seriously doubt the hs change. Definatly not enough to cause pressure on a load that didn't before.


Since your old Remington brass load also shows pressure now, have you had a decent temperature change in your neck of the woods? If you were running just below overpressure signs in the winter and now it's 40 degrees warmer outside, you certainly could show more pressure now.

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

From what I can tell on the barrel stampings, nothing looks to be wrong there..... Had they moved a tad, I'd likely never know. This is the most attention I've ever given to barrel markings....

No, temp change doesn't have anything to do with it. It was in the 40s when this pressure stuff started happening.

I should know more this weekend or first part of next week I hope. Waiting on a guy to get a 308 headspace gage in.

 

[Fisky]

Re: Out of Ideas!!!! High Pressure in Everything

Headspace checked out OK in the rifle. 1.5-2 thousandths if I remember correctly.

So, after that checked out I set my die up to bump shoulders back on once fired brass 2-3 thousandths. I then loaded up some once fired stuff at 45.5 (this was showing pressure before) and ran some new brass through the die and loaded some of that up as well. Fired 13 rounds and not a single sign of high pressure. I've read it on here MANY times, never set your dies up per the instructions, don't oversize the damn brass etc etc. I should have listened sooner I guess.

Going forward I will be bumping shoulders just enough to allow smooth chambering. It appears that has cured the problem for now. But I'm still confused as to why this would all of a sudden be an issue??? I've never had any issues before with the way I sized the brass. And the fact my "old Rem load" was showing pressure now and not before leaves me scratching my head. Something had to have changed to start all this. Either way, I got a new Redding FL bushing die coming and will do further testing with that and work my way up from 45.5 and see what happens I guess.

 

[Boltfluter]

Re: Out of Ideas!!!! High Pressure in Everything

Fisky,

All shell holders are not created equally. I.E. thickness. Are you using the same shell holder every time? Just a thought.

Regards, Paul.