MSR10 Hunter/Long Range owners

[Subwrx300]

Hey guys, have a favor to ask of other MSR10 owners. Specifically, those with rifles chambered in 6.5CM if possible.

I've got an issue with bullets unseating when chambered. Bullets start at OAL of 2.790 and come out of chamber at 2.82-2.84 by doing one of three things:

• Chamber round from magazine by releasing bolt stop
• Chambering round from magazine by manually cycling bolt with charging handle (full rack)
• Chamber round by firing and letting auto feed next round (normal fire)

If I single feed (push bullet all the way into chamber before dropping bolt closed, this problem is eliminated. Have a thread going in reloading section (https://www.snipershide.com/shooting/threads/bullets-unseating-in-ar10-when-chambering.6882188/) but a few other guys have tested this and do not have this issue but they are running other rifles with different BCGs and springs. So this is starting to point to an issue with the MSR10 as opposed to other semi autos.

Here's what I'm hoping you can do to test:

1. Use your normal resizing process on 3 pieces of brass. Write down neck diameter after sizing and neck thickness.
2. Load bullet (no primer no powder) at your normal seating depth.
3. Measure and right down each exact OAL for each bullet/case, loaded neck diameter.
4. Load those three dummy rounds into magazine
5. First round, chamber using bolt catch release
6. Second and third manually cycle aggressively to simulate firing.
7. Measure all three rounds OAL afterwards.

Please report back with type of brass, neck diameter, neck wall thickness, loaded neck diameter and oal change for each round if any.

Should only take 3-5min and could help out a bunch of other MSR10 owners of their is an issue with spring strength and BCG speed.

Thanks in advance!

 

[ScarlettRed]

I don't reload for 6.5 yet, but what you are describing is inertia (physics). An object in motion tends to stay in motion. Heavier bullets have more mass than little 556 bullets and love to jump. I have to taper crimp for my scar 17 to limit bullet jump and decided not to get a bigger semi auto platform because of this. Lowlight mentioned this issue with big bore semi's with firing pin slamfires. Same concept. Works just like a kinetic bullet puller. Three solutions are lower the bolt speed, lower the bullet mass or crimp the the bullets. Care must be used with crimping as it does increase pressures. I crimp to a slight jump as I believe it's very difficult to completely eliminate it without a large pressure spike. If I cycle a round in the field without firing it I reseat the bullet before the next session. I'd like to hear what others experiences are on the issue is as well. This is just my approach.

 

[Subwrx300]

I don't reload for 6.5 yet, but what you are describing is inertia (physics). An object in motion tends to stay in motion. Heavier bullets have more mass than little 556 bullets and love to jump. I have to taper crimp for my scar 17 to limit bullet jump and decided not to get a bigger semi auto platform because of this. Lowlight mentioned this issue with big bore semi's with firing pin slamfires. Same concept. Works just like a kinetic bullet puller. Three solutions are lower the bolt speed, lower the bullet mass or crimp the the bullets. Care must be used with crimping as it does increase pressures. I crimp to a slight jump as I believe it's very difficult to completely eliminate it without a large pressure spike. If I cycle a round in the field without firing it I reseat the bullet before the next session. I'd like to hear what others experiences are on the issue is as well. This is just my approach.

Definitely understand the physics of the why this is happening. However a few other guys on here have done this test with non-MSR models and found nearly no jump when chambering.

I've already increased neck tension to .005+ and taper crimp without success. Have heavier buffer and new spring coming to see if I can reduce but in either case, it points to an issue with the MSR stock configuration being too strong and in need of either aftermarket parts or an OEM fix. Problematic if your trying to use handloads with this particular rifle.

Maybe you can try with factory ammo to see if any changes in your system?

 

[ScarlettRed]

Different bullet weights, brass thickness, chamber tightness at the neck may explain others positive reports. However, bolt speed could create more momentum from one gun to the next. The MSR 10lr already is very soft shooting due to the long gas system. If you suspect all other factors being equal, your approach would certainly be worth trying. Suppressors could also speed things up a bit. I just figured it would be an issue I'd have to work around in my gas guns. I haven't checked bullet jump yet as I'm still shooting factory ammo. Where are you getting different buffers etc? MSR's are rather proprietary as I bought a JP silent captured buffer spring set for ar10 and it was a no go. When I get a chance I'll check factory ammo jump and let you know.

 

[Subwrx300]

Different bullet weights, brass thickness, chamber tightness at the neck may explain others positive reports. However, bolt speed could create more momentum from one gun to the next. The MSR 10lr already is very soft shooting due to the long gas system. If you suspect all other factors being equal, your approach would certainly be worth trying. Suppressors could also speed things up a bit. I just figured it would be an issue I'd have to work around in my gas guns. I haven't checked bullet jump yet as I'm still shooting factory ammo. Where are you getting different buffers etc? MSR's are rather proprietary as I bought a JP silent captured buffer spring set for ar10 and it was a no go. When I get a chance I'll check factory ammo jump and let you know.

I've tried three different types of brass, crimps, 4 different neck tension settings, 4 different bullets and two different mags. All of them exhibit the same issue to various degree. Minimum shift has been ~.005-.010" (Hornady brass with .005" neck tension) where max has been .050" (Starline brass with .003 neck tension).

MSR10 uses standard AR15 buffer (3.25" long, 2.95oz) but the carbine tube is Armalite style 7.25" long (the reason your SCS didn't work). The upper lower rear cut is Armalite style 45deg cut vs round of DPMS and the barrel/bolt are DMPS standard fit.
The AR 15 (not AR10) SCS "should" work if you can cut the rifle length spacer that came with your SCS to fit the gap in FRONT of the buffer when installed and drill a hole to allow the rod to pass through the center (with large clearance). This is the method that JP has offer to solve for Armalite carbine systems. Then you would have to swap the AR15 sprint for the AR 10 version. Spoke directly with JP Rifles about this specific solution today. I have an SCS for my AR15 that I'll be trying this solution on as a last resort.

However, I'm curious if JP would consider making a different face that adds material to the from of the SCS (about 1/4" or so) which would allow normal operation in Armalite tubes. I'm also considering swapping buffer tube to a standard carbine tube with a flatwire spring so that I can use the SCS instead of the Savage "Thor's Hammer" like spring/buffer.

 

[ScarlettRed]

I tested a factory hornady match 140eld round this evening. Took the firing pin out to be safe. Glad to see that is is retained under a spring. It jumped .005. This is pretty common in my experience with my scar 17. I crimp just enough to match that factory jump so as not to add too much pressure. I pulled the charging handle, paused and let it go. If it is the rifle's fault I would say the spring is too powerful, or the buffer mass too light as you suspect, however I don't think this phenomenon is out of the ordinary. I keep referring back to a kinetic bullet puller, if you slam the round, the bullet is going to move. There are so many factors involved in the rifle system that I'm going to reserve judgement on the solution. I would contact savage directly and maybe some other experts as I would be very interested if this can be remedied. I should note that mine is the MSR10LR so the buffer/spring may be slightly longer??? It has a prs gen 3 stock on it. It shoots real smooth so I may not upgrade to anything. I'll let you be the Pioneer and blaze the trail. Lol

 

[kombayotch]

I tried the first two. Range closes early here, so I could not test fire.

• Chamber round from magazine by releasing bolt sto

COAL grew by 0.0015

• Chambering round from magazine by manually cycling bolt with charging handle (full rack)

COAL grew by 0.0025 (same round)

This was an empty case loaded with a 140 ELD-M to 2.810". Used a Hornady bullet comparator to measure the ogive so that tip damage wasn't a factor.

 

[Subwrx300]

I tried the first two. Range closes early here, so I could not test fire.

• Chamber round from magazine by releasing bolt sto

COAL grew by 0.0015

• Chambering round from magazine by manually cycling bolt with charging handle (full rack)

COAL grew by 0.0025 (same round)

This was an empty case loaded with a 140 ELD-M to 2.810". Used a Hornady bullet comparator to measure the ogive so that tip damage wasn't a factor.

Awesome. Thanks @kombayotch . Can I ask how many rounds approximately through your rifle? I've got well over 2500 now and rifle is much looser than original. Bolt lock up is much easier now which may be contributing to why I'm seeing this now as opposed to early on during testing.

And I also saw less movement using Hornady brass versus Starline. Maybe a factor also since it seems much softer than Hornady: less tension even though it is being sized the same.

 

[kombayotch]

Only around 130 rounds. My reloads are Hornady.

 

[Mike_in_FL]

I hate to be the bearer of bad news but there's articles today saying the parent company, Vista Outdoors, is looking to sell off Savage now. So I would be beating on them quickly to see if they have a resolution or are even aware of the problem.

 

[Subwrx300]

I hate to be the bearer of bad news but there's articles today saying the parent company, Vista Outdoors, is looking to sell off Savage now. So I would be beating on them quickly to see if they have a resolution or are even aware of the problem.

Maybe they'll finally get some good QC again under new ownership!