35 Whelen AI Build Headspacing Issues

[Leaf Litter]

I recently put together my Tikka T3X/McGowen prefit 35 WAI and checked it with a go-gauge today just to have it not fit, and honestly it didn't seem that close to closing.

I removed the barrel last weekend and spun the new one on that same day. I ordered a rental go-gauge from 4D reamer rentals and it didn't work. The barrel is torqued to 90 ftlb as I've seen recommend. Could this be caused by anything other than a poorly reamed chamber?

I have an email sent to Mcgowen, but I assume I will not hear from them until Monday at the earliest and I've heard nothing but bad things about their customer service.

I'm trying not to get too upset, but it's definitely frustrating when things don't work. Anybody have advice on how to fix this situation with the least amount of pain and money expended?

Thanks in advance

 

[HandgunHTR]

It seem that whatever specs McGowan is using for their Tikka prefits, they are not correct. You are the 4th or 5th person that has recently posted about their prefit having short headspace.

If McGowan won't take of you, you can rent a reamer from 4D and finish it yourself. I have done a couple of short-chambered Mauser barrels and it really isn't that hard. I would bet that it is only a couple of thousandths off. If you have a set of feeler gauges you could get a rough estimate by spinning the barrel off a turn or two, chambering the go-gauge, turning the barrel back in until it stops and then measuring the gap between the action face and the shoulder.

 

[Wapiti1]

Before we all hang them, this is a wildcat with no industry standard prints. Mixing and matching reamers and gages will get you mixed results.

Is the gage you have a standard non-AI 35 Whelen GO gage for the headspace check? If it is the AI gage, do you know what chamber print it matches?

AI chambers are NOT standard length to the datum when compared to their parent cartridges. When properly chambered the standard Go gage is the max length, not the NO GO. The bolt should not close on the standard GO gage. It should be a couple thousandths short of that and stop hard if you try that gage.

Chamber new non-AI brass and see how it feels. The bolt should close, but be stiff. Not hammer it down stiff, but you should feel resistance. If that is the case, then you have a good chamber and can go forth and shoot.

Jeremy

 

[Leaf Litter]

Before we all hang them, this is a wildcat with no industry standard prints. Mixing and matching reamers and gages will get you mixed results.

Is the gage you have a standard non-AI 35 Whelen GO gage for the headspace check? If it is the AI gage, do you know what chamber print it matches?

AI chambers are NOT standard length to the datum when compared to their parent cartridges. When properly chambered the standard Go gage is the max length, not the NO GO. The bolt should not close on the standard GO gage. It should be a couple thousandths short of that and stop hard if you try that gage.

Chamber new non-AI brass and see how it feels. The bolt should close, but be stiff. Not hammer it down stiff, but you should feel resistance. If that is the case, then you have a good chamber and can go forth and shoot.

Jeremy

I agree, not totally blaming McGowen, just frustrated and trying to go through my options.

I don't currently have any 35 whelen ammo on hand, but standard 270 ammo fit in the chamber with no issue closing. I'm going to do some measuring with the mic today to see if I'm able to determine where the issue lies for certain. 35 whelen ammo is ordered to test that way.

 

[Wapiti1]

I agree, not totally blaming McGowen, just frustrated and trying to go through my options.

I don't currently have any 35 whelen ammo on hand, but standard 270 ammo fit in the chamber with no issue closing. I'm going to do some measuring with the mic today to see if I'm able to determine where the issue lies for certain. 35 whelen ammo is ordered to test that way.

So, you can't close on the GO gage, but can on a .270 case?

Am I reading all this correctly? If that is indeed correct, you are good.

Keep in mind, because it is a wildcat chamber, factory 35 Whelen ammo may work without any weirdness, or it might be snug. Different makers may behave differently.

Jeremy

 

[Leaf Litter]

Correct, it will

So, you can't close on the GO gage, but can on a .270 case?

Am I reading all this correctly? If that is indeed correct, you are good.

Keep in mind, because it is a wildcat chamber, factory 35 Whelen ammo may work without any weirdness, or it might be snug. Different makers may behave differently.

Correct, the bolt easily closes on 270 Win ammunition but not on the 35 Whelen AI go-gauge.

If the standard 35 Whelen ammo fits easily then I'll shoot it and measure the spent brass. Hopefully this is just a discrepancy between reamer and go-gauge.

 

[Randfal]

+1 on what those guys are saying. I have 2 35WhelenAI go gages(actual AI gages). One Manson and one PTG. There are .004” difference between the two. So which is right??? In the case of a Whalen AI default to the brass/round you’re shooting in it. You can’t place blame on this wildcat. If your 35w ammo fits,(ideally with a slight snugness) shoot it! If it fits with no resistance, a cheap an easy way to see how close to the boltface it is, is to put a piece of scotch tape on the brass head and see if you feel any resistance when closing the bolt (3m clear Scotch tape is about .003”thick). If you feel it, you’re within .003” and golden. Happy shooting! Love them 35s.

 

[Leaf Litter]

+1 on what those guys are saying. I have 2 35WhelenAI go gages(actual AI gages). One Manson and one PTG. There are .004” difference between the two. So which is right??? In the case of a Whalen AI default to the brass/round you’re shooting in it. You can’t place blame on this wildcat. If your 35w ammo fits,(ideally with a slight snugness) shoot it! If it fits with no resistance, a cheap an easy way to see how close to the boltface it is, is to put a piece of scotch tape on the brass head and see if you feel any resistance when closing the bolt (3m clear Scotch tape is about .003”thick). If you feel it, you’re within .003” and golden. Happy shooting! Love them 35s.

I have since decided that the situation is exactly as you described, mcgowen just uses the shorter version of 35WAI for their pattern. Standard 35W ammo fits as you described, just ever so slightly snug and seems to shoot relatively well.

I guess my only other concern will be how well the Redding 35WAI reloading dies fit compared to the Mcgowen chamber, but I guess that's the fun of wildcatting, right?

 

[Randfal]

I highly recommend getting a set of these Redding competition shell holders. They are sized in extra height from .002”- .010” increments. So you can accurately control how far your case goes into the die. I have over 60 sets of dies with lots of duplicates from different manufacturers and they all vary a little. Helps prevent pushing back shoulders too far or use them with your neck dies too.

 

[35WhelenAI]

I have since decided that the situation is exactly as you described, mcgowen just uses the shorter version of 35WAI for their pattern. Standard 35W ammo fits as you described, just ever so slightly snug and seems to shoot relatively well.

I guess my only other concern will be how well the Redding 35WAI reloading dies fit compared to the Mcgowen chamber, but I guess that's the fun of wildcatting, right?

Technically, the proper design of an AI chamber is to have slight resistance when chambering factory Whelen brass or factory ammo. McGowan's probably using the correct original 35 Whelen AI dimensions.

I have used a Redding 35 Whelen AI die for 22 years now. It works perfectly with fire formed brass from my chamber. I have it set to size the neck approx 80% of the neck length down toward the shoulder, and just kisses the case walls. Basically, I have it set to where brass chambers freely. That's what you want in a hunting round. I back off on the die more, I start to get a bit of resistance.

Fwiw, I started with a Brownells Shilen short chambered 35 Whelen bbl for my M98 action. The gunsmith used a Manson 35 AI reamer to turn it into the AI.

 

[35WhelenAI]

I have used a Redding 35 Whelen AI die for 22 years now. It works perfectly with fire formed brass from my chamber. I have it set to size the neck approx 80% of the neck length down toward the shoulder, and just kisses the case walls. Basically, I have it set to where brass chambers freely. That's what you want in a hunting round. I back off on the die more, I start to get a bit of resistance.

Fwiw, I started with a Brownells Shilen short chambered 35 Whelen bbl for my M98 action. The gunsmith used a Manson 35 AI reamer to turn it into the AI.