Freeze Plugs vs Valve Spring Retainers

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MatcoBill
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Freeze Plugs vs Valve Spring Retainers

Post by MatcoBill » Sun Jul 05, 2015 10:03 am

Which do you prefer and why?

a_canadian
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Re: Freeze Plugs vs Valve Spring Retainers

Post by a_canadian » Sun Jul 05, 2015 12:30 pm

I suppose if I were to build something as primitive as a freeze plug or valve spring retainer baffle system, I'd choose the valve spring retainers. Undoubtedly a high quality alloy, not mild low-carbon steel like the freeze plugs. Stainless freeze plugs might be a good bet and almost as tough as the valve spring retainers once formed owing to work hardening, but they're still rather thin and therefore cannot really be carved for proper efficiency via cross-bore jetting. The retainers offer more raw material. Even if all you have is a Dremel and some grinding bits you can detail the things in ways which offer better suppression while retaining a lot of durability.

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Re: Freeze Plugs vs Valve Spring Retainers

Post by c5_nc » Wed Jul 08, 2015 9:54 am

There was premature wear on the Freeze plugs cans I have seen personally, specifically separation on the face during the first 80 rounds on one, and wear to point that baffle strikes started happening on another around 400rds. When originally tested the formed FP sounded better than unmodified VR, when the VRs were modded they sounded better. Later I made and intricate Monocore and commercial like cone form 1s, while different sizes there is not an obvious advantage to one or the other in performance for the given tube size. Specifically I have a 8.9" VR can that is noticeably quieter than a AAC SDN6 and fairly close to the Liberty Freedom Ti (10" monster) and a 5.75" 8oz micro 308 can that is very quiet (for it's size and weight) with VRs.

The first iteration of my micro can valve retainer baffles (some further machining since then) a $5 M300 Tool Steel retainer

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Range Test of micro can (Gen 1) https://youtu.be/R9QsI7rgytQ

The first iteration of my 8.9" VR can baffles:
The dual clips ended up having no POI shift verses the SDN6 tested

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Range Test of Gen 1 version of this can: https://www.youtube.com/watch?v=CccZObvE3VM

The larger dual cliped ones had noticeable good redirection of the gas flow. Also testing later revealed little to no POI shift.

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A view showing the dual redirection

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This is the Second and Third time I took them apart and did some further mods:

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saigatechusa
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Re: Freeze Plugs vs Valve Spring Retainers

Post by saigatechusa » Fri Jul 10, 2015 9:11 am

Anyone use titanium retainers?

c5_nc
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Re: Freeze Plugs vs Valve Spring Retainers

Post by c5_nc » Fri Jul 10, 2015 9:33 am

saigatechusa wrote:Anyone use titanium retainers?
The stepped ones pictured above are Ti, nothing noticable wear rise so far.

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sub-sonic
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Re: Freeze Plugs vs Valve Spring Retainers

Post by sub-sonic » Fri Jul 10, 2015 10:15 pm

c5_nc wrote:There was premature wear on the Freeze plugs cans I have seen personally, specifically separation on the face during the first 80 rounds on one, and wear to point that baffle strikes started happening on another around 400rds.
can you explain the wear that caused the strikes did the holes wear smaller, or did the tube wear bent, or did the mount wear loose?
I have heard these stories but so far after 7 years no actual photos or other proof has been presented. I know about the full auto can killing that was done but that would have killed alot of home made silencers and alot of commercial models.

PS: I know every time this comes up I say show the proof and I am still waiting....7 years and counting
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MatcoBill
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Re: Freeze Plugs vs Valve Spring Retainers

Post by MatcoBill » Fri Jul 10, 2015 10:29 pm

even if the FP's don't last as long $0.69 a pop is way less than $20+ per VSR

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Re: Freeze Plugs vs Valve Spring Retainers

Post by c5_nc » Fri Jul 10, 2015 11:00 pm

MatcoBill wrote:even if the FP's don't last as long $0.69 a pop is way less than $20+ per VSR
Except they cost a $200 (for each one you replace) tax stamp if you were to replace them unless you have a SOT willing to do it.

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Re: Freeze Plugs vs Valve Spring Retainers

Post by c5_nc » Fri Jul 10, 2015 11:36 pm

sub-sonic wrote:
c5_nc wrote:There was premature wear on the Freeze plugs cans I have seen personally, specifically separation on the face during the first 80 rounds on one, and wear to point that baffle strikes started happening on another around 400rds.
can you explain the wear that caused the strikes did the holes wear smaller, or did the tube wear bent, or did the mount wear loose?
I have heard these stories but so far after 7 years no actual photos or other proof has been presented. I know about the full auto can killing that was done but that would have killed alot of home made silencers and alot of commercial models.

PS: I know every time this comes up I say show the proof and I am still waiting....7 years and counting
Sure. The can you asked about was quiet and accurate new. It was included in the POI and sound test comparison I did earlier this year and the rounds were off paper by then with tumbling rounds. Several light baffle end cap strikes after that. The rounds were destabilizing in the tube from the wear on the baffles. The baffles had worn to where they were quite a bit larger, and the end cap (made out of SS) was still that same bore of course. The plugs themselves show no signs of strikes only wear. I was asked to not post pictures of the stack, but I do have pictures of the end cap, and pictures and videos of the can being tested. The POI where it was off paper was done with about 300rds down the tube, the strikes at closer to 400rds. The can used a Titantium VR as a blast baffle, which showed no signs of wear.

Your older posts where the reason I went this route. The reason you don't see many pictures in general is because you can't replace freeze plugs (without a $200 per baffle tax stamp). My guess is some people may be skiping that and buying another $.69 part of the shelf. Which gives them a pretty good reason to avoid posting pictures. Another reason is many people don't show off failures. The SOT here in NC that replaces internals as a main business practice has posted that they had similar problems at lower round counts (I believe he said he looked like a dinosaur chewed on one set of low round count plugs), but that it it their company policy to only post stack pictures from commercially produced cans.

Here was one can I tested. The stack was taken out after the first range trip of around 80 rounds. The test platform was a 12.5" SBR with Tula 223/5.56. This can had a valve retainer as a blast baffle (m300 tool steel) that showed no signs of wear.

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Second one with some premature wear:

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This is from the POI testing I did, only the section on the can in question. The rounds shot this day were not on paper, and we found rounds tumbling although not strikes during the test that we knew of:

Apogee 5.56 (7.6" OAL)
https://youtu.be/KALg9p0NO3Q
Single clipped Freeze plugs lined up. Something is going on here. We were not on the target or even the large piece of cardboard (poster size). Shot another string centered to the cardboard and one on paper, tumbling. Bore looks consistent so not sure yet. It was not like this before when they were rotated 180 apart, they were lined up for this test. There wasn't a noticeable difference in sound. Direct thread.
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Someone on another board posted this a couple days ago out of their 400 round count tube. They had posted them publically and I am just sharing the links.

Less than 400 rds. 5.56 out of a 10.5" barrel.
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Close up of the first 2 baffles next to the last one.
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sub-sonic
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Re: Freeze Plugs vs Valve Spring Retainers

Post by sub-sonic » Fri Jul 10, 2015 11:50 pm

thanks for the pictures. first time I have seen any like that. any reason why the holes are off center in the bottom pictures?
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Re: Freeze Plugs vs Valve Spring Retainers

Post by gunny50 » Sat Jul 11, 2015 4:58 am

sub-sonic wrote:thanks for the pictures. first time I have seen any like that. any reason why the holes are off center in the bottom pictures?
My guess would be that they formed like in the bottom picture as the OP scooped the cones he formed in the freeze plugs.
I think one would not have that problem if one forms the FP like the Surefire baffles, Press them in a domed shape (use small trailer hitch) and use porting around to help gas deflection.

The weak / soft FP will deform faster from blast and powder residu, and being an a-symatric form due to the Scoop the problems only got bigger.
Gas and powder work on the sharp thin SOFT contact area.

But that is just how I feel about it.

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Re: Freeze Plugs vs Valve Spring Retainers

Post by c5_nc » Sat Jul 11, 2015 10:50 am

sub-sonic wrote:thanks for the pictures. first time I have seen any like that. any reason why the holes are off center in the bottom pictures?
That was his method of clipping, I assume it probably looked more defined prior to the wear.

On the can that had the strike (that I didn't post pictures of) the first rounds through it where 300blk subsonic and supers on a 8.2" barrel. When the testing showed the rounds tumbling we could not get the stack out at the range, when we started to tap them out the entire stack out at once. I was working on the assumption that the clips were misaligned. They looked pretty much like the "400rd freeze plugs" posted above, however I'm sure they where installed correctly then but the problems continued. The plugs I think are cold rolled A36 steel with a zinc like coating.

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Re: Freeze Plugs vs Valve Spring Retainers

Post by sub-sonic » Sat Jul 11, 2015 3:12 pm

I find this strange because I run my 5.56 can on a 16" barrel and always use SS109 FMJ and dont have this problem and I am into the thousands of rounds. The rifle is actually on its 3rd barrel and I run my 30cal can on a 18" FAL and a 16" SKS with surplus mil ammo and subs and on a bolt 7.62x39 with subs and all I got was some rust from (I assume) the commie SKS ammo. I get my cans hot enough to take the skin off your hand but I dont melt them
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