I need some serious help with my new rifle. I am very new to reloading(started 6 months ago). I have just started reloading for my Ruger M77 MkII and I cant quite figure out the proper seating depth. The Sierra book calls for a COAL of 2.350". I wanted to see what length my rifle needed so I seated my reloads to 2.400" and checked to see if the bolt would close. It did. So I backed off to 2.450". Bolt closed again with no problem. After about 4 attempts I finally hit the throat. 2.580" was what I came up with. I am no where near an expert but this cant be anywhere close to correct. Any ideas on what is going on? Im pretty damn lost at this point.

I have the same rifle and I also found it to be longer throated than the factory loads indicate....

I just load my bullets seated out to magazine length and am just happy with it...

Mine has been a tack driver even at 300yds with factory loads, and even better with handloads and decent bullets....

Seated further out also lowers pressure...

YOur confusion is strictly because you are trying to apply what all the "experts" are trying to tell ya... and your rifle differs from that...Ruger knows what they are doing....It is just where you want it to be!

Cheers
seafire

I wouldn't worry about it and just seat them at 2.350". I like to seat my 300 just off the lands and thought I'd try it with my 22-250 when I got it but discovered that when the bullet is touching the lands, the bullet is barely in the case and you generally want at least the bullet diameter depth in the case. I ended up just seating them at 2.350" according to the manual and still have been able to accomplish one hole groups with the right load.

Got the same problem with my .22-250. I've had to seat the bullets out because when seated to 2.350, I don't have the accuracy I want. Seating out to 2.5+ limits my bullet usage, but it does give great accuracy. Those long bullets also carry better at the longer ranges.

I have a custom 22-250 that shoots very well with bullets seated .010 off the lands. I'm getting 3 shots into 1/4" at 100. It's my most accurate hunting rifle. I'm shooting 55gr Sierra HPBT bullets, Benchmark powder and Federal 210M primers.
Don

This is my method. I got from a tech at Hodgdon Powder a couple decades ago. Start with your most accurate load. Find the point at which the bullets are just touching the lands. To do this load a bullet into an empty and unprimed case-make a dummy round. Shine the bullet with steel wool so you can see the marks from the lands on the bullet after you chamber it. Adjust your seating depth until the marks from the lands appear square in shape. This is your starting point. After a couple fouling shots, I fire at least two groups at this seating depth, run one wet patch through the barrel, a dry patch, then I test the next seating depth, which is .005 off the lands. The next will be .010 off, and so on. If your barrel is fairly accurate and you are as well, you should see changes in your group size. At some point you will find your most accurate seating depth, then groups will open up again, then they will get smaller again. At this point you are done testing seating depth. I have a .300 that used to shoot best with bullets seated to touch the lands. That rifle now has considerable throat erosion and shoots best with bullets .025 off the lands. It will soon get a new barrel. My 22-250 shoots best at .005 off the lands. My .243 shoots best with bullets touching the lands, then the groups tighten up again at .025 off. These rifles are all sub-moa shooters, but are not bench rest guns. I once had a Ruger 7 mag that shot around 1.5". Nothing noteworthy. I found a powder charge that cut those groups to around 1". Tinkering with seating depth brought the average three shot group, using Matchking bullets and weighed and prepped brass, to .4".Thats 4/10ths, consistently, for exactly 11 shots after one fouling shot. Shot 13 would be out of the group every time. Any more if I have an accurate rifle to begin with, testing seating depth is a standard part of my load development routine.

quote:

Originally posted by Laner:
I wanted to see what length my rifle needed so I seated my reloads to 2.400" and checked to see if the bolt would close. It did. So I backed off to 2.450". Bolt closed again with no problem. After about 4 attempts I finally hit the throat. 2.580" was what I came up with.

Most factory chambers are long throated. In fact in my experience, it is rare to find one which is not. This is probably some sort of a safety measure against high pressure from the fatories' side??

Be aware that when your bullet is seated so far out (in your case 2.580), that you can't close the bolt any more, you are way into the lands already. You will be able to seat at or into the lands, and still close the bolt with comparatively little resistance. This is NOT a very accurate method for finding your max cartridge length, and at worst it could be unsafe.

Get yourself a Stoney Point seating depth gauge, or use one of several other methods described in reloading books or on Internet forums like this to establish your seating depth. If you insist on relying on the "close bolt" method, make sure you examine the bullet with a magnifying glass to establish when you hit the lands.

There is nothing wrong per se with seating into the lands, except that it raises your pressure, so you normally need to back off a bit on your charge weights.

- mike

My longest cartridge in .22-250 is 2.560" with a Nosler 55gr. Ballistic Tip. That doesn't leave me much neck to grip the bullet, but since I load everything in single shot fashion there's no problem. The manufacturers today are making the chambers ridiculously long. It's as if they never heard of SAAMI recommendations or merely don't give a damn. Since the Nosler BT is a very long bullet that means that with some shorter bullets I can't even reach the lands. Best wishes.

Cal - Montreal

I have a remington vs 700 in 22-250 and I went about it this way. First, I used chamber micrometer to check the length of the chamber and throat. It indicated that the rifle was in the middle of the sammi scale. I then loaded five rounds at the barrel lands, five .010 off the lands, five at .015, five at .020, and five at .025. After shooting all in 5 shot groups, I determined that .015 off the lands was the best group, by far. That was with 52 gr. hornady bt match over 39 gr. of H-380 with a federal bench rest primer.

Roger, from what I've read, that seems to be a very successful load it the 22-250. Mine does best with 38.7 gr H380 and bullets seated .005 off the lands. I'm using 52 gr JLK low drag bullets. The rifle (Cooper) has shot many sub-1/2 MOA groups, with one of the best being a 2.33 five-shot at 650 yards. My seating depth testing is basically identical to yours. I have a Kimber .243 I need to get back out and confirm with more groups. Initial testing gave me a 1/2" five-shot. I would be thrilled to get this kind of accuracy from a 5 lb rifle.