Tell me what's wrong..

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Pyd

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I just made three 5 round groups with my Swift.
I did the candle test 25 times and got and average OAL of 2.778.
Started with 2.775 on first load, decent group of 1.25" @100.
Second load I went to 2.752. 2" group with vertical stringing.
3rd was 2.760 OAL, shot a heart stopping 1/2" group. I am in heaven.
Except.. These rounds are not feeding through my Ruger M77 without a gentle thumb put to start them in to the chamber.
I like the group, showed me the old gun isn't burnt out, but this feeding issue has me confused.
Thoughts?

Worth noting, book said my load would be 3800, my chrony said 3950.
 
What bullets are you using? 0.008" change in OAL resulting in that much difference in group size is pretty extreme.

As for the feeding issue, the book spec is 2.680", so you are quite far out there. I would bet this is the cause.
 
For the vast majority of factory rifles, the lands are quite far from touching the bullet when loaded to SAAMI specs. This is a safety margin, aka the "lawyer throat"

A good rule of thumb for seating depths when hand-loading is to have at least one caliber worth of the bearing surface of the bullet inside the neck. How much do yours have?
 
I have been loading for the Swift since about 1977, and have owned at least 6 rifle so chambered, most of them M77V Rugers.

Your speed of 3950 with a 50 grain bullet is not out of line, in my experience. Most Swifts I owned would make ½ moa, some even slightly less.

With the 50 Ballistic Tip, I was able to achieve that velocity with several powders, including IMR 4064, IMR 4007 ssc, Vihtavuori N140 and 540, Reloder 15, H380, and W760.

Your seating depth is well out there, but that is not unusual, either. Too bad they do not feed well. I did not experience feeding problems with any of my Swifts.

Regards, Dave.
 
Here's a few observations , you can take them as you will or dismiss them.
One 5 shot group is a good place to start but you should try and duplicate it several times before calling it a done deal.

As far as the length goes , COAL is number that should be taken off the ogive if one wants to be super accurate, not the tip of the bullet, I'm not sure here you are measuring from.
However as long as the length of you hand loads are constant it's all good .

Now for the feeding, I don't quite understand when you say you have to use some thumb pressure.
when do you have to push it and where, do you mean straight down at the back to get the cartridge angled up so the bullet will run up the ramp better?
Cat
 
What I found is that the bolt would not hot the back of the case to start the feed, I would start the feed with my thumb on the shell and the bolt would pick it up. I didn't have to move it far, just a half inch or so.
 
I am wondering if your bullets are just too long to function in the mag. Make up some dummy rounds to 2.68 as mentioned above and see how they cycle.

might want to double check there is no crud interfering with the mag follower.
 
May very well be a length issue.
Gun is clean, I was meticulous before I started load testing.
Not liking have to trade an awesome group for a few thou of clearance.
 
May very well be a length issue.
Gun is clean, I was meticulous before I started load testing.
Not liking have to trade an awesome group for a few thou of clearance.
 
Pyd said:
What I found is that the bolt would not hot the back of the case to start the feed, I would start the feed with my thumb on the shell and the bolt would pick it up. I didn't have to move it far, just a half inch or so.
Click to expand...

Is the follower plate in the magazine properly attached to mag spring? Is mag spring properly attached to floor plate? Cartridges should be picked up if bolt is pulled back far enough.
 
Pyd said:
What I found is that the bolt would not hot the back of the case to start the feed, I would start the feed with my thumb on the shell and the bolt would pick it up. I didn't have to move it far, just a half inch or so.
Click to expand...

I think that is more of a magazine problem than a cartridge problem!
Without actually looking at the rifle however it is pretty hard to diagnose stuff like this.
What happens if you only put one round in the mag?
Cat
 
And to expand on what cat said, does it happen with all the rounds in the mag, only the first, every one from a certain side of the mag? It sounds like the bolt isn't coming far enough back to catch the case head. That's very odd to me. Would be much easier with the rifle in hand.
 
Not feeding is mostly likely a mag follower spring issue and nothing to do with the OAL. Even though it's 20 thou short. Look in the mag well for something that's interfering with the follower.
The manual reflects conditions with the rifle used in the tests only. Most likely a universal receiver with a different barrel length and rifling twist than your Ruger. Not something to worry about.
 
Yep, looking like a gun issue.
However, I have reloads that cycle just fine, it is my new loads that are acting up.
Same brass, just cleaned and sized.
Here, if you look close you can see the rear of the case is down a bit, while the front is where it is supposed to be. That small gap that grows from the front of the case to the back, grows as you look farther back at the case. I can apply pressure to the front of the shell, which in turn raises the rear, allowing the bolt to engage the case.
Second photo is just my bolt riding over the case, which is the problem.
There is no contact on the bullet itsself, as mentioned by most of you, the OAL is not the issue. Lots of clearance in an area one would suaspect the front would hit and drop the rear, not happening.
So..
Exact same brass cycles unsized through the gun, my FL sized brass does not, may be a clue..
Still not getting this..

20150208_153108_zpsdeozxnr6.jpg


20150208_153158_zps622xa17x.jpg
 
looks to me like the OAL of your cartridge is to long for tha magazine and the tip of the bullet is hung up frocing the back of the cartridge down
 
r204 said:
looks to me like the OAL of your cartridge is to long for tha magazine and the tip of the bullet is hung up frocing the back of the cartridge down
Click to expand...

I know. But it's not. There seems to be a lot of clearance between the bullet/case and anything it can touch, nothing is making contact.
I am losing sleep over this..
 
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