GSPHunter Wrote:Hi LR1955, What is the source of your belief that the compound throat would be eroded "probably in less than 1,000 rounds." The .5 degree throat extends for ~.150" with ~.110" of 1.5 degree after that. Do you believe that the throat angle is off any long term significance? I'm not necessary disagreeing with you, but I am wondering if you have any hard data involving compound throats to support your opinion

LR1955 Wrote:Guys:

You are confusing what I said about throat erosion with wearing out barrels. I bet that both designs of throat wear out barrels of the same make equally. 8K rounds or in that arena somewhere for the compound throated barrels and conventional throated barrels. Some would care and others not. Depends on what they use the rifle for.

Perhaps a better way to describe my statement is that I believe that you will see enough throat erosion with about 1K rounds fired so as to make any benefits from a compound throat be reduced or perhaps even eliminated. This depends on how someone uses his rifle. A IPSC guy who blasts magazines in rapid fire will wear one out much faster than a guy who shoots a hundred rounds a year slow fire.

Until someone out there does some chamber casting before and after along with some info on their bullets, loads, and general wear and tear such as rapid fire or slow fire, I bet this is exactly what happens. I would say a throat erosion gauge would probably give an indicator as well. However, a person would have to get two barrels made by the same place but with both throats, then shoot both the same way using the same loads.

As for Wildcats, there is nothing 'Wildcat' about a .295 neck in a Grendel chamber. Or a .300 neck. You use the same loading dies set the same way and given a decent functioning rifle or carbine, the brass works just fine in each.

LR55

JASmith Wrote:One way to explore the throat erosion question might be for folks with 1,000+ rounds through the SAAMI Grendel to re-check maximum COL with the same bullet design and measuring techniques as their records show at the start.

BjornF16 Wrote:LR55

Are you suggesting that the short throated "Grendel II" will hold up to the same proof testing that AA performed? What about bolt life?

Edit: Perhaps "Wildcat" is the wrong term...substitute variant if you like. My point is short throating in particular nullifies the safety testing done on the original cartridge. Just read some of the ridiculous velocities and standard deviations those with the "improved" chamber were getting.

Without AA's quality control of the pre-SAAMI Grendel, and without the SAAMI specifications, there is no guarantee of what you are getting in one of the variant chambers.

(...and yes, I understand that there will be some mfg issues that would cause even a SAAMI chamber to be outside of specification...)

LR1955 Wrote:Bjorn:

When someone tells me something is 'short throated' I take it to mean who ever chambered the barrel made a mistake and cut it too short. I have had barrels that were short throated and got them reamed out to the right or at least safe dimensions.

I will say that I have both types of throats on my Grendels and if I handed them to you or anyone else here with a few factory loads and asked them to shoot both, that it would be a 50% chance anyone would be able to tell which one was which.

I wonder how many variants of .308 and 5.56 chambers are out there?

BjornF16 Wrote:Gene, IIRC, a certain company was marketing their "variant" with a short throat as a "design" feature that resulted in higher velocities (or at least their mouthpiece was representing them in that fashion).

That tells me it isn't a mistake...

Then there is the Type 1 vs Type 2...I can't even keep that straight.

My POINT was: Getting a SAAMI Grendel is a known quantity; whereas the variants aren't necessarily known (or consistent) quantities.

BjornF16 Wrote:The mouthpiece is banned...I cannot search his posts (and I'm not going to spend hours re-reading the lead up to the dust up over chambers).

I certainly haven't said that the compound throat was Nirvana, and all others don't perform. On the contrary, I ordered a "Grendel Match" (.295 neck) for my bolt rifle. It shoots factory ammo fine, but I certainly measured the chamber/throat before sending any factory rounds downrange (my objective is to hand load for this rifle).

There are a lot of folks who show up here asking questions that don't necessarily have the tools or knowledge to validate a non-SAAMI chamber (of course, some do; I'm not trying to cast aspersions to all newcomers). I'm merely suggesting the safest bet is to go true Grendel since it is now SAAMI/CIP'd (and I haven't suggested that AA has said anything else is unsafe).

I fully understand that quite a few match shooters (or anyone else chasing extreme accuracy) may order shorter throats in their quest for accuracy; that reamers wear; that some out there don't like to admit mistakes; etc.

LR1955 Wrote:Bjorn / Guys:
My problem is that new guys to the Grendel are starting to get the idea that anything other than a .300 / compound throat chamber (which apparently defines the Grendel in technical terms) is dangerous. This myth is compounded by who ever thought up the Grendel I and II stuff. We never had problems discerning the difference before this I and II stuff. And before the cartridge got SAAMI certified, we rarely or never argued the merits of each or their safety. This is because we knew that we could not tell the difference between the two unless using the shortest possible bullets or the longest possible bullets. We used the same OAL that Alexander recommended and never had problems with either.

LR1955 Wrote:Here is a question then.

You can buy one of two barrels. You know that wait times for barrels are measured in years, not months (not unrealistic).

One is a .264 LBC made and guaranteed by Les Bear. The other is a Grendel marketed as a Stoner or Liberty sold from one of the reputable mail order places.

Both are the exact length and taper you want and both are the same price.

Which one would you buy?

cory Wrote:The "Grendel II" chamber was nothing more than a cover your ass exercise by the company you should have seen mentioned in the "jiberish". That company put out a lot of economy barrels with short throats, did not meet the SAAMI spec, that were potentially catastrophically hazardous to the shooter. Rather than admitting their mistake, recalling the barrels and replacing them, they took the stance that they were within spec and the problem was the design of the Grendel Chamber. However, they were going to take the "higher" ground and offer to ream out your chamber to a "better" chamber. There's a lot of bad blood between AA and Satern that explains some of this.

The "Grendel II" is actually one of the many chambers Bill A. experimented with until he settled on the Grendel chamber with the compound throat for best accuracy through a wide range of bullets.

The compound throat is a design solution that is unique to the Grendel. I maybe mistaking about it being unique, but at most it's rare. It has shown to be extremely effectiver. However, reamer makers sometimes hate it because it makes their jobs more difficult.