358 Win BDL Feeding Issue

[keags]

Hello all,

Hoping for some help with an infuriating feeding problem. When I moved to Iowa I re-barreled my 308 to 358 Win so I could continue to hunt with it.

As a 308, this gun had no feeding or ejection problems. Unfortunately as a 358, it now has a huge problem: when the bolt is run quickly, the cartridges jam against the mouth of the chamber. See the below photos:



And the following videos (Youtube links):

358 Feeding Issue Video 1
358 Feeding Issue Video 2

Defiance Deviant action, Wyatt's BDL cut, Wyatt's mag box and follower, red hawk rifles BDL bottom metal, pac-nor 358 win barrel. It shoots great and headspaces perfectly so the barrel doesn't seem to be the issue. When the bolt is run slowly, it works fine. When I cycle 308 rounds through the rifle, they feed and eject perfectly no matter hard hard I run the bolt (although I obviously don't fire them).

Things I've tried:
- Bending mag box lips narrower (made the rounds pop out too soon which caused a different type of jam because the back end kicks up and the front nose-dived below the chamber and jammed)
- Bending mag box lips wider (made the problem worse/jams more frequent)
- Tried both round nose and spire point bullets (round nose are worse, but SP exhibit the same issue, just less frequently)
- Replaced wyatt's box, spring, and follower with Remington factory mag box, spring, and follower (no change, same issue)
- Bending spring to put more force on the nose of the cartridge (no effect)
- Making the spring weaker by grinding off some material at the bends (no effect)
- Simulated a stronger spring by pushing the spring upwards with my fingers from the bottom while running the bolt (no effect)

My assessment: I think that because the bullet and neck of the cartridge are so fat, when it hits the feed ramp, it tips up much higher than a 308. And because the round is so short, the tip of the bullet doesn't enter the chamber until it has already tipped up too far, at which point it jams.

So I think I know what is happening, but I have no idea how to fix it.

I know, I know - buy a Tikka . I love me my Tikkas but would love to get this rifle back up and running. Anyone have any ideas? Am I just screwed and need to abandon the hope of using the 358 with this setup???

 

[Luke S]

I had a 358 Ruger American. My feeding was never that bad but it did seem like the fatter cartridges were an issue. I switched to 450 BM 3 round mags which happen to work for 308. No issues until I changed to a 308 barrel.
So, is there a single stack mag available for your rifle? I think that would work.

 

[tt_johnsclist]

Your assessment is probably right, and Luke S is on to something. Modifying the magazine to a single stack, modifying the follower at the bottom of the mag, or making the feed ramp more gradual would be the next steps. You may also still have to narrow the feed lips on the mag a tiny bit as well.

 

[JCMCUBIC]

I had the same issue. I used a Wyatt's center feed box and it was ok but irksome in that it needed to be loaded from the bottom. It wasn't perfect but it was usable...most of the time.

The fix was to go M5 bottom metal and 3 round flush fit AICS mags. It fixed everything.

 

[keags]

Thanks guys!! Sounds like switching to a DBM is the strong recommendation.

Looks like HS Precision makes a DBM for regular BDL inlets (my stock doesn't have an M5 inlet, unfortunately). Looks like it's a double stack but center feed which seems like it should resolve the problem of the round tilting sideways. Seems like an easy thing to try before modifying the feed ramp as a last resort.

I shall try to acquire one and report back!

 

[JCMCUBIC]

I've not used HS's BM, so I'm can't speak for or against it.

Lots of companies will inlet any non-plastic stock to M5 though. AICS is "fairly" standardized so you have lots of options if you go that route. HS is limited to their proprietary mags which is a one and only route which may end up being more expensive in the end.

 

[keags]

I've not used HS's BM, so I'm can't speak for or against it.

Lots of companies will inlet any non-plastic stock to M5 though. AICS is "fairly" standardized so you have lots of options if you go that route. HS is limited to their proprietary mags which is a one and only route which may end up being more expensive in the end.

Ah good to know - this is a Bell and Carlson fiberglass stock, so presumably that would be an option here. Good point about the proprietary vs standard mags. Will look at inletting options for this. Thank you!

 

[keags]

Reporting back - I hit the easy (and fast) button and ordered the HS Precision bottom metal. Not perfectly flush like the BDL bottom metal, but not overly obtrusive. It did take some Dremel work on the B&C stock to get it to fit, as HS precision said that it would, but it fits nicely now.



Good news - the rifle now feeds cartridges with spire point cartridges perfectly. I cycled over 300 (dummy) rounds from the magazine through the rifle as hard and fast as I could without a single failure. I tried 200gr SP interlocks, 200gr FTX, and 225 grain sierras, all worked flawlessly.

Unfortunately... it still does not feed cartridges with round nose bullets (I tried 200gr round nose interlocks and sierra pro hunters). As before, the bullets tip up too quickly and jam against the top of the entrance to the chamber, when the bolt is run fast.

However, I can make peace with this and just use spire point bullets in this rifle. Excited that this fixed the problem, thank you everyone for the help!!

As an aside, I was curious if this problem would exist in other rifles. I don't have another 358, but my Tikka in 6.5 creedmoor can feed these rounds most of the way into the chamber (they obviously stop when the bullet starts to enter the neck area of the chamber) so I was able to partially test it.

Interestingly, the TIkka also jams the (358 cal) round nose cartridges against the mouth of the chamber when run hard and fast. This makes me suspect that most (all?) magazine fed bolt action rifles would likely struggles with 35 cal round nose bullets, because they are so fat and short that they tip up and jam. I'm sure there are exceptions, and I'm also sure that one could modify a feed ramp to feed these bullets better, just my observations from a sample size of two.
Thanks again to all who steered me toward a center feed DBM, much appreciated.