Loading for a Sako .243

[RainDodger]

I have a Sako L-579 Forester, heavy barrel .243. 1:10 twist ratio, and it definitely likes bullets on the light side. It's a beautiful rifle dated to the early 1970s. Now that I've gotten to be an old guy, I can spend a lot more time figuring out why I've never gotten it to shoot like it should... and I think I have. Until recently, groups have been a couple of inches.... not Sako-quality. Perusing some of the varmint shooter's forums, I saw that a lot of guys were having to load their Sako rifles long - jamming the bullet into the lands. Not a practice I've been fond of, but nothing else has worked to date.

I loaded up 5 rounds of each: .015” off the lands, .010” off, .005”off, AT the lands, and then jammed into the lands .005”, .010” and .015”.

All my short cartridges shot normally. Kind of fist-sized spreads, nothing to write home about. The 3 groups into the lands got successively and noticeably tighter and they pressed further into the rifling. The cartridges that were .015” jammed into the lands produced a group under an inch at 100 yards. This has been repeatable. The 2 longest loads are nearly equal so I’m going to work on them a little, but I think I should have it shooting under an inch. All of this likely explains why it shoots some factory loads quite well – turns out the rifle has an extremely short throat and factory rounds were usually jammed way in into the lands.

Anybody have similar findings with a Sako?

 

[243winxb]

I bought one from a guy years ago. When i looked it over, i noticed the barrel was sitting in the barrel channel funny. Barrel was sitting high & tight against the left side of the forearm.

I said it looks like the barrel is bent. He agreed. Bought it for very few dollars, with scope.

As soon as he was out the door, i had the action out of the beavertail stock.
Seen the problem right away.

Someone added a swivel stud to the forearm. One that looks like a big wood screw. They screwed it in without removing the action. This is what pushed the barrel up and left.

Trimmed the stud screw a little below the channel surface. Ready to test fire.

Loaded up 20 rounds of my pet load, IMR 4350, Sierra 85 gr hpbt #1530 . Shot 4 groups, 5 shots each. Averaged right close to 3/4" &100 yards. A keeper.

But already owned a 40xb in 243. So in the sale rack it goes. (Guns are ALWAYS on sale.)

A couple weeks later, guy looks it over. Likes it. Will i take a Ruger #1 hb 243 in trade? Sure, thats why i am here.
I said to him, the Ruger isnt very accurate , is it. He agreed. Deal done. It was a 2" rifle.

But had nice wood, wood sells. Sold.

Jam- i dont remember my standard load hitting the rifling. I avoided a jam in the Rem 40 xb after needing to unload at a shoot. Bullet stayed in the rifling. Powder stayed in the action. No more jam.

Injoy you rifle.

 

[BBarn]

I've worked with a Browning made by Sako. It doesn't have a short throat. So it seems to be different than yours.

I doubt there is any significant difference between the rounds jammed 005", .010", and .015".: There isn't enough neck tension to jam bullets further into the rifling. The bullets will slip back into the case as the bolt is closed and end up at the same point.

 

[RainDodger]

I would tend to agree with you Bbam… I thought the exact same thing. When first loading the rounds, I chambered each length, to test for that exact thing. No problem with bullets remaining in the rifling. In fact, it's very strange that there are no marks on the bullets from the rifling, but the loads are all verified lengths with a chamber gauge. I don't understand it, but it's working.