[robinsok]

So i am loading my first rounds for my Tikka tonight and have a question. My hornady manual lists max for this cartridge really low compared to what i have read everywhere. I believe it is because they don't publish modern pressure data because it wouldn't be safe in the old military guns.

Question is.

My data is.

Grafs Brass
Hornady 129 gr Interlock SP
Powder is IMR 4350 stepped up at 43.5, 44, 44.5, and 45 grains. I have read several accounts of guys who claim that 44 and 45 grains IS about their sweet spot with a 129 SP.
C.O.L., i have set at ~2.92.

Does this sound about right?


Also, something i haven't encountered before, (only other round i load is .223) is the bullet compressing or contacting the powder somewhat.

On my lower charged loads here, there is space between bullet and powder, on the higher ones, it may start to make contact. Does this step pressure up more than what you would obviously expect due to the higher powder charge?

Thanks for the help for a reloading newbie.

 

[fredj338]

I wouldn't worry much about slightly compressed loads w/ 4350. I shoot a 260ai, sim to the 6.5. I pretty much run slower powders & all my loads are compressed 99-105%. Since the 6.5x55 is an older round, many booos hold back on their pwoder charges for the older rifles. The Nosler manual isn't as conservative as Hornday.
Nosler has 45.5gr as max w/ 125grNP. So work up until you see pressure signs & back down from that as a working pressure range. You OAL will vary w/ your gun. As long as the bullet isn't hitting lands, OAL doesn't impact pressure much but can affect accuracy quite a bit.
I haven't hunted my 260ai yet, it's a heavy target rig, but w/ bipod, it could be an exc antelope or beanfield deer round. I would look to the 125grNP or 130grNAB for a hunting bullet @ closer distance. I find Hornady bullets pretty soft for higher vel impact in most calibers. You might also try H4350, I find it more accurate than the IMR & it's a bit slower for higher vel.

 

[robinsok]

Thanks Fred, little update here. I am not sure that the powder even in the 45 grain load is actually compressed, although i'm not totally sure how to tell. I know when i shake the round, i still here a little powder movement, although not that much. I would think that if it were compressed, there probably would not be much sound, but maybe this method doesn't mean a thing, i dunno.

I went out to test the round tonight.. Got to my location and set up and the wind started gusting pretty bad. I had nine rounds loaded in each of the powder levels, only shot three of each because with the wind, i'm not sure how much of my accuracy or lack thereof, is the round, and how much is the wind.

My best group actually came out of the lowest charge, 43.5, had two rounds touching and the next roughly .5-.75 inches off, which could easily be due to wind. I don't think i am going to try and draw too many conclusions from tonight test because of the wind, but i couldn't help but try them since i had already driven out and set up and all. From there, the groups seemed to get progressively worse. The 44.5 and 45 grain rounds didn't even group within 3 inches.

The only other guy i know who shoots a swede says he reloads his rounds pretty mild because that's where the accuracy is in his rifle, i don't know yet if I am running into the same thing or not.

My question is, what do I need to watch for for signs of pressure? I can't tell if i have flattened primers or not. I may post some pictures and see what you think.

 

[fredj338]

Every rifle is diff but many do shoot better below max loads. JME, I have never gotten my best loads using Hornady bullets in several calibers. Try changing your OAL after you settle on one load that looks good, then try swapping primers. Sometimes it matters & sometimes it doesn't. My 260ai shoots most powder & bulelt combos well, some really well, some crazy good accuracy. It's a trial & error thing. Always start w/ the bullets for accuracy, then powder, then OAL, then case prep, then primers.

 

[creophus]

I built a Mauser and chambered it for 6.5 Swede. I've not developed my consistent load yet, so I can't comment on accuracy.

Good on ya for getting that Tika in 6.5x55!

 

[robinsok]

I built a Mauser and chambered it for 6.5 Swede. I've not developed my consistent load yet, so I can't comment on accuracy.

Good on ya for getting that Tika in 6.5x55!

Thanks man! I like it.

So here are my results. I'll add again that the wind was swirling when i shot these, and i only shot one group of three rounds out of each batch, didn't want to waste too many rounds with the wind how it was.

All loads are the same as listed in the original post with the exception of the powder charge, written on target.

And here are the fired cases, anyone see problems with the primers "flattening"? I can't tell that there is a problem, these are 43.5, 44.0, 44.5, 45.0 top to bottom.

So assuming I stay with the 43.5 grain load with this bullet, what should i look at next to improve the accuracy? Longer OAL? I matched the OAL on these rounds to the OAL of the factory rounds that are very accurate in my gun, some hornady soft points that have shot a three round group that i covered with a dime.

 

[PCJim]

First, I would never base an accuracy load on a three shot group, but that's just me. Five shot minimum to try to eliminate flyers that I might have created, that are not the fault of the load.

If you feel you've found the right charge, you can vary it 0.1 or .2gr up and down to see if the group improves. Then, test the COL to find the length the rifle prefers.

The method I use - take a casing that was fired in the rifle you want to test and resize only the neck (short stroke a FL die by a nickel width). Take a dremel cutting wheel and cut two slits in the neck lengthwise and opposite (180 degrees) each other. With the particular bullet that you want to test, just barely seat it in the modified neck. There should be enough tension remaining in the cut neck to hold the bullet firmly, but loose enough that the bullet will be shoved further into the case when it contacts the rifling.

Carefully chamber this modified cartridge, then remove it just as carefully so that the bullet does not contact any part of the chamber in a way that could effect the results. Measure and record the COL. This is the distance to the rifling with this particular bullet's profile/length. Pull the bullet back out of the case, as long as possible, and repeat the COL measurement two or three more times until you are comfortable that you have a hard COL. Now, experiment with this particular bullet being loaded anywhere from 0.005 to 0.03" (maybe more?) off the rifling to see where your most accurate load is.

Keep in mind that this procedure is good only for one specific bullet. Changing from one manufacture's bullet to another, regardless of weight/profile, requires you to retest the COL to the rifling.

Patience will pay off. It is an involved procedure, but will result in an ideal load for that particular bullet/charge/rifle combination.

 

[fredj338]

First, I would never base an accuracy load on a three shot group, but that's just me. Five shot minimum to try to eliminate flyers that I might have created, that are not the fault of the load.
Patience will pay off. It is an involved procedure, but will result in an ideal load for that particular bullet/charge/rifle combination.

It depends. For target or varmint rifles, a 5 shot group is more telling. For a big game rifle, consistant 3 shot groups, w/ the first cold shot always on is fine. I have never fired more than two rounds ever at a game animal. When you are dealing w/ larger bores & more recoil, it's more the shooter than the gun & good 5 shot groups are harder to gcome by.:supergrin: