Need some help with my first 308 reloads - sticky bolt/ flat primers, low velocity

[Jeg181420]

I just finished my Savage 308 build. It's my first long range bolt action rifle that was somewhat of a budget project. It started out as a Stevens 200 in .223 and used only the action and the bolt (swapped bolt face and magazine). Ordered a SSS competition trigger, McMillan A5 stock, Northland barrel nut, Northland recoil lug, EGW 20MOA base, and a new 24" factory varmint barrel that I bought of someone on Snipershide. I borrowed a set of PTG gauges to set the barrel headspacing and I am confident that I did it correctly. Once everything was put together, I took the rifle out and fired about 25 rounds of 147 grain Silver Bear to test function and to get my scope (10X SWFA) on paper. The rifle functioned perfectly.

About a month later, I decided to start reloading and I ordered 100 pieces of once fired Lake City brass (most likely fired through a machine gun), a box of 175 grain Sierra MatchKings, a box of Winchester Large Primers, and a 5 pound jug of Reloader 15 as well as a Lyman 49th Edition manual, Lyman case gauge, RCBS Rock Chucker kit, RCBS dies, and a chronograph. I did a lot of research and watched a bunch of youtube videos before I got started. Anyway, I set up the press and dies as per the instructions (screw down until it meets shell holder and then another 1/4 turn in so it cams over) tumbled the brass, and began resizing. Next, I trimmed all the brass to 2.005", chamfered and deburred. Finally, I set up the RCBS pocket swager die and removed the primer pocket crimps. Dropped every piece of brass into the case guage and they all fit perfectly.

Then I set up the hand priming tool to begin seating my primers and realized that I swaged too much. There was literally no resistance at all when I squeezed the tool. I went online and was told to try tapping the brass at a 45 degree angle to see if the primer backed out, which it didn't so I figured I was ok. I started with 15 rounds of 41.0 grains RL15 and planned on working up from there if necessary (keeping in mind the smaller case capacity of LC brass). The OAL of each round was 2.80". Here's where things started to go south. After firing each round, the bolt was stuck and i had to stand up and pull the bolt handle up and then use a rubber hammer to tap the bolt handle rearwards to extract and eject the spent casing. The primers were completely flat but the readings on the chronograph were only in the range of 2460-2510fps (tested chronograph with some .223 50 grain VMAX and was getting around 2900 fps so I know the unit is reading properly). Each 3 shot group size was about .75" at 100 yards. I was able to chamber, extract, and eject unfired rounds with no problem whatsoever. The problem only happens once the round has been fired. I was thinking about reducing my load but I feel like that would put me in the low 2400fps range, which won't do me much good, especially when I have the opportunity to shoot with my friend at his private 1000 yard range. Does anyone have any idea as to what could be causing this problem? My friend told me that LC brass fired out of machine gun sometimes won't work reliable in a bolt action rifle even after resizing and that I should try new Winchester brass. Another person told me that I could have a tight chamber that needs to be polished. I think its the loose primer pocket.

Summary - 24" Savage rifle shoots factory ammo just fine but my reloads (41.0gr RL15, 175gr SMK, LC brass trimmed to 2.005", 2.80" OAL) flatten the primer and make my bolt stick even though the velocity is only in the 2460-2510fps range. I think I swaged the primer pockets to hard because it requires no resistance at all to seat a primer with the hand tool. I think this may have something to do with the problem.

 

[308Gunner]

You might try winchester brass also do you have a FL sizing die? There will be someone that will give you a good place to start. Good luck

 

[Jeg181420]

Yes I used a FL sizing die on the LC brass. I just picked up some Winchester brass from Cabelas today and will process it over the weekend. Hopefully that will give me better results.

 

[CavReconScout]

My Savage 10TR has a really short chamber. Have you checked yours by chance? I can only load my 175's to 2.750, and 41.5 grains of Reloader 15 runs around 2500 fps out of the 20" barrel with excellent accuracy.

 

[Jeg181420]

not sure. is there any way to measure the chamber? As I said in my OP, the only other ammo that I ran through the rifle was 147 grain silver bear which is obviously shorter than the 2.80" OAL with the 175 SMK. But on the other hand, I have no problem cycling live rounds through the rifle. The problem persists only once the round is fired.

 

[buffybuster]

Not sure the cause of the stuck cases, but if you set your headspace with the PTG gauges and you setup the FL die per the instructions, chances are you are oversizing your cases and the headspace on those cases are on the excessive side. However if that LC brass was MG fired, there may be other issues.

 

[van462]

Be sure and look for a shiny ring about 3/8" to 1/2" above the case head. Machine gun fired brass usually stretches just above case head. Poor mans meathod to set up a sizing die is to take a fired case. Cycle it into the chamber, you should feel resistance. Back off sizing die and screw adjust it to where the bolt handle just closes smoothly on the sized case.

 

[mtrmn]

I was unaware the RCBS swager could be adjusted to swage too much. The swaging ram should be properly sized to only swage to a certain size sufficient to be able to seat a primer. Take a piece of NEW uncrimped brass and see if the swaging ram will enter the primer pocket by hand with very little resistance. If not, the ram may be a bit oversized.

Too much headspace can cause these "overpressure" symptoms and fool you into thinking the load is too hot. Try backing off the die like van462 suggests.

 

[Rhino79]

The first place I'd check is your sizing die. I would check the length if the case from the datum line against your reloading manual. I believe it should be around 1.560, but check your manual to be sure. You may already know this but just because it slips in and out of your case gauge doesn't mean it's properly headspaced for your specific chamber. Some LC brass may need to be resized further using a small base die, but after processing thousands of LC 762 brass, I've never had to do this for my rifle. I'd also suggest that until you get this figured out, to keep your charge weights in a safe area and wear appropriate safety gear because a flat primer and a case which is hard to extract are signs of over pressure.

 

[No1]

I'll first say that I don't shoot 308 bolt guns, but I have seen similar problems in my gasser.
Your low velocity is due to your 41.0g of R15. That is a starting powder charge and I would expect it to chrono at about 2500 or less.
The flattened primers are likely the lower pressure too and/or excessive headspace. 1. when the primer fires it ignites the powder 2. as the powder burns it expands and pushes the primer out of the primer pocket proud of the case headand into the bolt face 3. as the powder continues to burn and builds up pressure it deforms the primer and the case is now being setback as well. All of this giving the appearance of a high pressure flattened primer even though the pressure is quite safe. I've seen this during load development with H335 and Varget in the 308. As you approach higher pressures this symptom goes away.
Others have already covered the sizing, but for an autoloader I would fully size the case body the first time and set the shoulder back about .005" less than my measured chamber. That's the nice thing about LC brass, it's a little long to start with so I can fit it to my chamber from the get go. After that, minimal sizing with a little shoulder setback is all that will be required.

 

[280nosler]

I see that you have either bought of are buying Winchester brass. I have found that once fired mg brass in 308 is workable, but completely not worth it for a bolt gun. Start with virgin brass, and work up a load. If you have a adjustable primer press, set it is it absolutely flat with the base. Mg brass has been known to have slightly loose primer pockets, which can actually flatten the primer because it does not have enought pressure on the sides to keep it in place.

Secondly, I use RL15 in my 308 (when I can find some). I shoot 155-168's exclusively. Not that there is anything wrong with heavier bullets, but my rifle does not like them. It is what it is. That said try some lighter bullets and see how it goes. My load of choice with the 168's was 43.5 grains.

Best piece of advise is to take a piece of fired brass (from your rifle), and just barely begin to size it, and remove from the die. Take a virgin bullet and insert by hand, and it should be loose fitting enough so that with your pinky, pushing down on it will seat it further. If you have redding bushing dies, a 338 or 339 could do this. Take said bullet (that is void of powder or primer) and carefully load it into your chamber. Lock bolt into position (fully closed) then remove the round slowly so the bullet does not make contact with anything. Measure said round. Do this 3 more times, or until you get the same reading for your measurement. From there, back off the seating between .010 to .020. Note this length and bullet combination. This should be done for any bullet you plan to load. Make a set dummy round (I use fired berdan primed brass that has been body sized, and mark it read and write the bullet on the casing).

Lots of tricks to the trade, so don't hesitate to ask.