Help - Load Damaged My Bolt

[barlowrs]

Hey Everyone, I am looking for any insight you may have. I have been reloading casually for years, and just picked up a new Tikka T3x ultra lite in .270 for this season. I am working on developing a load for her now but have run into some strange issues.

First about the load:

Bullet: Barnes TTSX 130gr
Brass: Federal once fired (case volume measured after fire formed at 69.10 gr H2O).
Case Size: Full length sized with a 0.002" shoulder bump (measured using Sinclair shoulder tool)
Case Prep: Brass trimmed to 2.5300, primer pockets cleaned and flash hole deburred.
Primer: Standard Large Rifle - Silver is CCI, Gold is Winchester
Powder: Ramshot Hunter (Suggested load range is from 51 - 56.6 for TSX, assume about the same)
Seat Depth: 0.062" off Lands. Initially i shot for 0.05" off lands per Barnes suggestion, but would not clear my magazine, so I kept seating until they worked in my mag.
OAL: 3.367"

I have never used Ramshot before, but its all I can get my hands on these days.



So I have two issues:

1. I loaded 10 rounds with what would have been a mild load just so I could get velocity numbers to calibrate my GordonsReloading tool data. This load used the CCI primers and 52.2 gr of Ramshot, all other parameters are above. The issue is that despite this being in the low end of the suggested powder charge range, As you can see in the photo below, I was getting high pressure signs already (primer is flattened). This load was giving me an average velocity of 2,866.6 with a SD of 23 ft/sec which seems to be pretty close to what this weight should give in terms of velocity.

Why am I seeing high pressure signs? should I start lower but then have a slow .270 round? Is something else wring with my load?



2. I loaded 10 more rounds (Win Primers) starting at 54.4gr and increasing 0.2 gr each shot to look for nodes. on two of my shots, a pinhole blew out of the back of the primers (at 54.6gr and 55.2 gr). I have heard years ago Winchester had quality issues that resulted in something like this, Could this be caused by that or something wrong with my load. (These primers are pretty old!). Note I stopped at 55.0gr which gave a max velocity of 3,071 ft/sec.



Lastly, is my freshly fluted Bolt ok??!! It has 4 small dimples in it now!

 

[barnfrog]

I have no answers for you and can't help but ask one glaringly obvious question.

After seeing an obviously flattened primer at 52.5 grains of powder, what possessed you to go up more than two whole grains and continue up from there?

 

[barlowrs]

I have no answers for you and can't help but ask one glaringly obvious question.

After seeing an obviously flattened primer at 52.5 grains of powder, what possessed you to go up more than two whole grains and continue up from there?

That would be stupidity, plain and simple.......I assumed the charge was so low, I wasn't looking at primers or for signs of damage. just recording chrono numbers and sending the next one down range.......

 

[edwardware]

Primers leak when pockets are loose or occasionally when loads are over pressure. In your case, you're over pressure on the basis of flattened primers. This might be a bit worse if headspace is excessive but you haven't presented data to validate that.

Your bolt won't grow back, but it's fine and unharmed. I have rifles with similar flame cutting, and I have rifles that's show max pressure very, very low in the recipe range.

Pay more attention to primers and snug pockets, and carry on.

 

[243winxb]

Winchester made a lot of defective primers years ago. As you know. Change brand of primer.

Loose pockets from over pressure loads, look the same as defective primer, almost.
The primers that vented, remove them from the brass. A loose pocket will etch the whole side of the primer.

The pock marked bolt face is not a problem on my guns. Just looks bad.

I will have to check load data to comment on your loads.

 

[243winxb]

54.6 would be my maximum.

Ramshot Hunter (Suggested load range is from 51 - 56.6 for TSX, assume about the same)

Barnes data is even hotter.

I would not trust any data for this brand of powders.

 

[243winxb]

OAL: 3.367"

270 winchester?

Barnes has 3.250" ? What am I missing? Edit 3.340" is saami max. Never mind.

 

[Nature Boy]

Loose pockets + Winchester primers + overpressure loads = etched bolt face

 

[barlowrs]

270 winchester?

Barnes has 3.250" ? What am I missing? Edit 3.340" is saami max. Never mind.

Thanks for all the input above! My OAL is something I am unsure about actually since I am longer than spec, however, in my mind, the deeper the bullet is seated, the higher the pressure would be, so having it longer should show less pressure, correct? Or am I thinking about that wrong? I know if you are jammed in the lands you get a high spike, but I am a ways off the lands, so that shouldn't be the problem.

 

[N555]

Book COAL is just a suggestion. My 6.5creedmoore loads are 0.088 to 0.1 over book COAL, they probably won't feed or chamber in any other gun.

 

[AJC1]

Most monos are supposed to run at +.050 to the lands. Have you read the information from the company and applied it to your loads. It's been very warm, is your ammunition sitting in the sun during testing? Your seeing pressure on primers, is there any heavy bolt lift or extraction...

 

[AJC1]

Thanks for all the input above! My OAL is something I am unsure about actually since I am longer than spec, however, in my mind, the deeper the bullet is seated, the higher the pressure would be, so having it longer should show less pressure, correct? Or am I thinking about that wrong? I know if you are jammed in the lands you get a high spike, but I am a ways off the lands, so that shouldn't be the problem.

There is a middle range that reduces peak pressure. To deep higher pressure, into the lands higher pressure. Monos usually need a longer run at the lands due to taking more push before yealding.

 

[barlowrs]

Most monos are supposed to run at +.050 to the lands. Have you read the information from the company and applied it to your loads. It's been very warm, is your ammunition sitting in the sun during testing? Your seeing pressure on primers, is there any heavy bolt lift or extraction...

Barnes suggests 0.050 off the lands, but in my gun, that ends up being too long OAL and the rounds will not fit into my magazine. IN order to make them fit my magazine, I seated them deeper to an OAL of 3.367' which gives me a 0.062" jump.

 

[243winxb]

the deeper the bullet is seated, the higher the pressure would be, so having it longer should show less pressure, correct

Without pressure test equipment, it's a guess. But did see 1 test, deeper showed less pressure.

Many magnum cartridge chambers have a long free bore to reduce pressure. This can be seen in Weatherby rifles. So for Rifles, the longer the jump to the rifling, less pressure. My guess.

Handgun seem to be the opposite. Deeper= higher pressure. My guess. COULD be all wrong.

Primer in loose pocket. Gas cutting started at bottom of cup. Internet photo.

Bottom line- Dont use the Winchester primers while working up the load.

 

[Slamfire]

Just cut the loads till the primers stop leaking and etching your bolt face. I don't know why primers leak, I would have thought they were flexible enough to expand with the case pocket. Gas gets between the cup and pocket at high enough pressures, for reasons I don't know, but I don't believe it is due to "weak primers". It is due to too high of pressures. Never had bolt etch with light loads, only happens with hot loads. And probably your loads are within book values. But your gun don't know book values, it only knows itself. Cut the loads back a couple of grains, if not five, and see if you have problems.

I am going to say, I have conducted extensive load development, ten shot groups over a chronograph, carefully monitoring velocity, primer condition, and bolt lift. And after thinking I have developed a good, near max load, after shooting that enough of that load, I always find over pressure indications. Which results in cutting the load.

At least the primer did not pierce and dish the firing pin. I will bet Tikka firing pins are not cheap. While standing at the USMC Armorer trailer at Camp Perry, a shooter asked how many pierced primers did it take to ruin an AR15 primer, and the Armorer said he had seen firing pins ruined with one pierced primer. Tell you want, dish a pre 64 firing pin badly enough, and a replacement is going to be hundreds of dollars.

As for your bolt, I don't know how much bolt face etch requires a new bolt face. Just don't shoot more loads that do cause bolt face etch, if you can!

Developed this load, shot well at the range, fast and accurate



took the rifle to CMP Talladega, and this is what this load did later



Cut that load down by two grains.

This is an old military bolt, seen a bit of both face etch. Still useable.




I never ran "hot" loads in my M1a's. I never saw evidence of primer leaking, and yet, there was. No idea what so ever other than gas must be venting before the primer cup fully seals.



It was not something to be worried about when GI bolts were $35.00 to $50.00 each



Today, these bolts are going for much more!

 

[2ndtimer]

To echo 243winxb, those are the classic Winchester defective large rifle primers, enjoy your engraved bolt face. Using the CCI primers should eliminate future pock marks to your bolt face. Clearly you have learned your lesson to closely examine each fired case as you gradually work up your load. It also is a painful lesson that what may have been a safe load in Western Powder’s rifle (probably a custom barrel in a universal receiver) may not be a safe load in YOUR rifle. Alas, your rifle may not reach the velocities they did with that powder.
I have loaded my .270 Win (a bargain MarlinXL-7) with Hunter and the Hornady 130 gr SP up to 56.5 gr for just over 3,000 fps from the 22” barrel at 80 degrees F. I have never loaded the Barnes or other mono metal bullets, but I can see where the bullet construction may have an effect on pressure. My primers (CCI-200 and Federal 210) were pretty flat too, at maximum loads, but I had no ejector marks on the brass and bolt lift was easy.
Different rifles, different bullets and probably different conditions, which is why your mileage may vary. I would not hesitate to use Ramshot Hunter in my .270 Win, except that I am getting better accuracy with Alliant Power Pro 4000-MR, although Hunter was very close and certainly acceptable for my hunting purposes.

 

[Blue68f100]

I would re check to make sure you are not jammed into the lands. Even though you had to reduce the length for it to fit the magazine I would recheck all my number just to make sure I did not flip any digits. As you seat the bullet deeper into the brass your reducing volume which will increase your pressure.

Recheck, then back the load way off. Try again with a reduced load and work back up if not pressure signs. Are your sure your using rifle primers and not pistol?

 

[Swampman]

Winchester rifle primers went to hell in a handbasket when they quit nickel plating them (it was late 90's IIRC).

.257 Roberts Improved loads that had been fine with the old plated primers did some serious etching on my SAKO's bolt face after the change.

Switched to CCI BR-2's and no more problems.

 

[Charlie98]

I've had the same issues with Winchester large pistol primers in .41MAG loads... and also, a little further down the pressure scale... .45ACP, so it's not always hot loads that will pierce them.

It did a number on a few of my guns...

Marlin 1894 .41MAG bolt face...



S&W 58 recoil shield...



The culprits...





I had used 3 other bricks of these same primers prior without issues, this 4th brick gave me all the problems. I still have the 5th brick... I was going to return it to Winchester, but I wanted replacement primers, not money. So, instead I just kept them for That Day when I have nothing else. Needless to say, I don't use Winchester primers anymore.


Looking at the OP's problem from another direction... I have a Browning 71 in .348WCF. The Brownings have a notoriously short rifling leade... although I didn't find this out until just a few years ago. Loading the Hornady 200grn JSP bullet, over H4831, at the bottom start load... I was getting pressure signs and a sticky lever. I reduced 3grns from the start load and got to where the primers weren't smashed flat, and the lever dropped like it should. Knowing now what I didn't know then... I'm sure the bullets were if not jamming the rifling, they were certainly close. Even the front driving band on cast bullets (RCBS 200grn FN) sticks the rifling... so it's right there. Now that I understand it, I can accommodate it, but when I was a noob to the .348, I didn't understand what I was doing wrong.

 

[Blue68f100]

I've had the same issues with Winchester large pistol primers in .41MAG loads... and also, a little further down the pressure scale... .45ACP, so it's not always hot loads that will pierce them.

It did a number on a few of my guns...

Marlin 1894 .41MAG bolt face...

View attachment 1102900

S&W 58 recoil shield...

View attachment 1102901

The culprits...

View attachment 1102902

View attachment 1102903

I had used 3 other bricks of these same primers prior without issues, this 4th brick gave me all the problems. I still have the 5th brick... I was going to return it to Winchester, but I wanted replacement primers, not money. So, instead I just kept them for That Day when I have nothing else. Needless to say, I don't use Winchester primers anymore.


Looking at the OP's problem from another direction... I have a Browning 71 in .348WCF. The Brownings have a notoriously short rifling leade... although I didn't find this out until just a few years ago. Loading the Hornady 200grn JSP bullet, over H4831, at the bottom start load... I was getting pressure signs and a sticky lever. I reduced 3grns from the start load and got to where the primers weren't smashed flat, and the lever dropped like it should. Knowing now what I didn't know then... I'm sure the bullets were if not jamming the rifling, they were certainly close. Even the front driving band on cast bullets (RCBS 200grn FN) sticks the rifling... so it's right there. Now that I understand it, I can accommodate it, but when I was a noob to the .348, I didn't understand what I was doing wrong.

Was all your lot numbers the same? I've had some bad LP primers in the past. Olin, paid for the repair and replaced the primers 2 for 1. I had a 10k lot that became 20k of a know good lot.

 

[BBarn]

Given the flattened CCI primers at 52.2gr., it doesn't seem surprising that an additional 2.4+gr. of powder would pierce primers, regardless of brand.

The results shared by the OP also reinforces my belief that the concept of "book velocity means you are at book pressure" for a given cartridge and powder is unreliable (unless the chronograph used was reading a few hundred fps low or there is something seriously wrong with the rifle).

Perhaps double check that the bullets are indeed .277" and 130gr., (and not 7mm (.284")).

 

[illinoisburt]

Given the flattened CCI primers at 52.2gr., it doesn't seem surprising that an additional 2.4+gr. of powder would pierce primers, regardless of brand.
......
Perhaps double check that the bullets are indeed .277" and 130gr., (and not 7mm (.284")).

Have to agree here. Say what you will about Win LRP (I had a bad batch myself with duds) the fact that the CCI was flattened with less powder tells us there is too much pressure regardless the primer. I agree it would be a very good idea to mic the bullets and put a couple of check weights on the scale to start. Then checking bullets in the lands or not could be as easy as putting a wrap of masking tape on a finished round and seeing where the rifling engagement is starting.

 

[Charlie98]

Was all your lot numbers the same? I've had some bad LP primers in the past. Olin, paid for the repair and replaced the primers 2 for 1. I had a 10k lot that became 20k of a know good lot.

They were all from the same 5K primer case... but I don't know if each box had the same lot number. Winchester didn't mention anything about swapping primers 2:1, but I had read more than one recent experience where Winchester only gave them something like $60/1K as reimbursement... not primers. I don't know if that's true or not... I didn't pursue it.

 

[Charlie98]

Perhaps double check that the bullets are indeed .277" and 130gr., (and not 7mm (.284")).

I was kind of wondering that meself...

 

[jmorris]

My OAL is something I am unsure about actually since I am longer than spec, however, in my mind, the deeper the bullet is seated, the higher the pressure would be, so having it longer should show less pressure, correct?

Seating depth and pressure do not have a linear relationship.

Conditions exist where seating the bullet deeper can increase pressures just the same as running it further out. Kind of the point in “maximum” and “minimum” depths. Not that that’s the limit of where you can put it but the limit they suggest you do, using their data.