Help - 270 Load damaging 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!

 

[JFK]

I don’t have any experience with that powder, but I’d bet the issue is your seating depth. Are you very confident in your measurement to lands? Your COL is over .100 what Barnes suggests in their load data. I load to max charge with that bullet in my 270 (albeit with H4350) where my COL is shorter than book, and no pressure issues.

The one time I’ve had a pressure issue with a Barnes bullet was having them seated too long. Blew primers. Seated them .050 deeper and problem went away.

I’d re-seat them to book COL and see what they do. Hunt down some h4350 or 100V as those are pretty much the go-to powders for those bullets in 270.

 

[barlowrs]

I don’t have any experience with that powder, but I’d bet the issue is your seating depth. Are you very confident in your measurement to lands? Your COL is over .100 what Barnes suggests in their load data. I load to max charge with that bullet in my 270 (albeit with H4350) where my COL is shorter than book, and no pressure issues.

The one time I’ve had a pressure issue with a Barnes bullet was having them seated too long. Blew primers. Seated them .050 deeper and problem went away.

I’d re-seat them to book COL and see what they do. Hunt down some h4350 or 100V as those are pretty much the go-to powders for those bullets in 270.

Seating deeper (shorter COL) would increase the pressure and make it worse wouldn't it? I will run a few LIGHT loads with my longer COL and the suggested COL and see if it improves or worsens the issue. thanks for the input!

 

[Hackleback]

Over pressure for the combination- and dangerous. Start at 51 gr (or what ever the recommended starting load is), might be worth looking at load date from another source to double check. Old brass (hardened) or loose primer pockets (did the primers easily seat)??

 

[barlowrs]

Over pressure for the combination- and dangerous. Start at 51 gr (or what ever the recommended starting load is), might be worth looking at load date from another source to double check. Old brass (hardened) or loose primer pockets (did the primers easily seat)??

Primers felt good when seated. And other data I looked at for this powder actually suggested an even hotter load. (Barnes data suggested 52.5 to 58.4 gr). Brass was once fired factory ammo

 

[9.3koolaid]

Seating deeper (shorter COL) would increase the pressure and make it worse wouldn't it? I will run a few LIGHT loads with my longer COL and the suggested COL and see if it improves or worsens the issue. thanks for the input!

It's counterintuitive but I think it can be the opposite in some cases. Seated closer to the lands the bullet is sealing off the explosion almost immediately whereas if there is more of a jump there will be some blow-by until the bullet has hit the rifling and sealed off the barrel.

 

[Hackleback]

Bullets too close to the lands (or jamming bullets into the lands) can cause high pressure conditions. Coppers like a lot of jump, so as mentioned, suggested COL (or shorter with a sub max load) should be investigated (assuming this is not a compressed load)

 

[waldo9190]

Don't have my notes at work for CBTO measurement, but using that same powder/bullet combo (CCI 200 primer, starline brass) in my T3 SS my rifle settled in at 56.6 grains with no pressure signs.

Also, looks like something may be out of spec with your primer pockets? My guess is those dimples/spalling on your bolt face is from hot gas escaping through that pin hole at the edge of the primer in your first pic. I've seen some awfully flat primers and some heavy ejector marks before but never seen that.

 

[theddguide]

I'd be looking for a new rifle. But that's just me. Lol

Sent from my SM-G950U using Tapatalk

 

[30338]

Winchester owes you a bolt face. Its pretty well documented about their crappy runs of primers that leaked gas and pitted bolt faces. Stop using those immediately. Get your Lot#(s) and contact Winchester. They'll want to see your pics.

Then I'd contact Shooter71 and getting your bolt fixed. Sucks for sure, but contact Winchester.

 

[willfrye027]

Couple things. Your bolt looks damaged, needs to be at least checked out by a smith.

Federal brass is super soft and will blow a primer faster in general. Looks like gas leaked around the edge of the primer pocket and did not actually pierce the primer.

Ram shot hunter is a good powder but pretty temp sensitive. If your rounds sat in the hot sun, hot chamber, etc and you are already close to max pressure that can be enough to do it.

Changing seating depth is not going to dramatically reduce your pressure and make this a safe load. Start over.

 

[barlowrs]

I'd be looking for a new rifle. But that's just me. Lol

Sent from my SM-G950U using Tapatalk

Na, I am actually very happy with this rifle. She is very nice and actually shoots well when I get things dialed in. This was some plinking reloads I had previously made for my Rem 700 that I just ran through her when I was getting the scope sighted (these are not hunting rounds, hence why I am developing hunting rounds for her now). 6 Shot group at 100 yards and 4 shot group at 300 yards

 

[barlowrs]

It's counterintuitive but I think it can be the opposite in some cases. Seated closer to the lands the bullet is sealing off the explosion almost immediately whereas if there is more of a jump there will be some blow-by until the bullet has hit the rifling and sealed off the barrel.

This is what I am suspecting. I know that she liked some reloads I made for my other 270 which I used to sight her in (see above post), so I think I will mimic that seating depth with a min charge and see what happens. I will do a 5 shot group that mimic the length to the Ogive (so bullet jump is same as my other rounds) as well as a 5 shot group that mimics the OAL and see what happens.

 

[kota]

I don’t load for a 270 and didn’t look up data, so take this FWIW, which probably isn’t much. .062 off the lands seems pretty short for a reload, at least compared to some of my stuff that is .005. It’s not like you are shooting really long, heavy for caliber bullets and intentionally trying to wring every single FPS out of it either, so why don’t they fit in your magazine? I would double check your measurement of where the lands is, and also the dimensions of your brass after it’s been fired in your rifle. Are your measurements not accurate, is your chamber long, or the throat really that long?

Does factory ammo show the same pressure signs (looks like you have ejector marks or what should be a starting load?)

If that checks out, I would revisit your loading process. Sizing due adjusted properly, scale calibrated, flash holes not too big etc.

If that checks out I would either send it back to tikka or a smith depending on if it’s new or not. Had a buddy that nicked the lands with a segmented cleaning rod. It created a burr and the rifle blew primers on previously safe loads until the burr was removed.

 

[willfrye027]

This is what I am suspecting. I know that she liked some reloads I made for my other 270 which I used to sight her in (see above post), so I think I will mimic that seating depth with a min charge and see what happens. I will do a 5 shot group that mimic the length to the Ogive (so bullet jump is same as my other rounds) as well as a 5 shot group that mimics the OAL and see what happens.

Don’t yourself. If you keep shooting at that powder charge you are going to keep blowing out primers. Deeper seating may actually increase your pressure as you are decreased case volume. Even if you are jamming the bullet in the lands, backing off if NOT going to give you a safe load.

Your charge/brass/primer combo is WAY over pressure.

 

[30338]

More info on defective Win primers on this thread.

Winchester primer problem

I recently had this issue with my Winchester Large Rifle Primers in a 6.5-284. Out of 20 bullets shot, 10 had pierced the rounded edge of the primer, pitted my bolt face and deformed my ejector pin. I’m sending them in to Winchester for a look at the primers. KNL192G is the lot I’m having...

www.longrangehunting.com

I'll suggest calling Winchester again. Review the pics in this thread. Same issue OP is having. Winchester owes you new primers and a repaired bolt face.

 

[JeffRaines]

Don’t yourself. If you keep shooting at that powder charge you are going to keep blowing out primers. Deeper seating may actually increase your pressure as you are decreased case volume. Even if you are jamming the bullet in the lands, backing off if NOT going to give you a safe load.

Your charge/brass/primer combo is WAY over pressure.

OP - heed this warning. Look at where your eye and head is in relation to that bolt when you're pulling the trigger.

Not trying to be harsh, but it isn't worth your sight, limbs or life. Get the rifle inspected, bolt replaced if need be and START OVER.

 

[49ereric]

Throw away that brass and switch brands and start over.

 

[Tjay]

primer is flattened, This is not always caused by high pressure. It can also be low pressure with the primer backing out at the start and then being slammed back in as pressure peaks.
Winchester had a large run of primmer issues like this, pinhole causing bolt face pitting.

I have used up to 57 gr. Hunter with 140 TSX bullets in Fed. brass.

 

[SDHNTR]

STOP SHOOTING THAT LOAD AND GUN!

You are at super dangerous levels of pressure! Go get that bolt face cut true, or replaced. And have your chamber inspected by a competent gunsmith. I’d also scrap all components and start over. You likely have bad primers, but could also have moist powder, bad brass, a chamber burr or carbon ring, etc. Get the gun inspected and repaired. Then start over with all new components, at a starting load!